Add m-esr52 at 52.6.0

1 files changed, 1724 insertions, 0 deletions

diff --git a/dom/html/nsGenericHTMLElement.h b/dom/html/nsGenericHTMLElement.h
new file mode 100644
index 0000000000..3cca41c3d7
--- /dev/null
+++ b/dom/html/nsGenericHTMLElement.h
@@ -0,0 +1,1724 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+#ifndef nsGenericHTMLElement_h___
+#define nsGenericHTMLElement_h___
+
+#include "mozilla/Attributes.h"
+#include "mozilla/EventForwards.h"
+#include "nsMappedAttributeElement.h"
+#include "nsIDOMHTMLElement.h"
+#include "nsNameSpaceManager.h"  // for kNameSpaceID_None
+#include "nsIFormControl.h"
+#include "nsGkAtoms.h"
+#include "nsContentCreatorFunctions.h"
+#include "mozilla/ErrorResult.h"
+#include "nsIDOMHTMLMenuElement.h"
+#include "mozilla/dom/DOMRect.h"
+#include "mozilla/dom/ValidityState.h"
+#include "mozilla/dom/ElementInlines.h"
+
+class nsDOMTokenList;
+class nsIDOMHTMLMenuElement;
+class nsIEditor;
+class nsIFormControlFrame;
+class nsIFrame;
+class nsILayoutHistoryState;
+class nsIURI;
+class nsPresState;
+struct nsSize;
+
+namespace mozilla {
+class EventChainPostVisitor;
+class EventChainPreVisitor;
+class EventChainVisitor;
+class EventListenerManager;
+class EventStates;
+namespace dom {
+class HTMLFormElement;
+class HTMLMenuElement;
+} // namespace dom
+} // namespace mozilla
+
+typedef nsMappedAttributeElement nsGenericHTMLElementBase;
+
+/**
+ * A common superclass for HTML elements
+ */
+class nsGenericHTMLElement : public nsGenericHTMLElementBase,
+                             public nsIDOMHTMLElement
+{
+public:
+  using Element::SetTabIndex;
+  using Element::Focus;
+  explicit nsGenericHTMLElement(already_AddRefed<mozilla::dom::NodeInfo>& aNodeInfo)
+    : nsGenericHTMLElementBase(aNodeInfo)
+  {
+    NS_ASSERTION(mNodeInfo->NamespaceID() == kNameSpaceID_XHTML,
+                 "Unexpected namespace");
+    AddStatesSilently(NS_EVENT_STATE_LTR);
+    SetFlags(NODE_HAS_DIRECTION_LTR);
+  }
+
+  NS_DECL_ISUPPORTS_INHERITED
+
+  NS_IMPL_FROMCONTENT(nsGenericHTMLElement, kNameSpaceID_XHTML)
+
+  // From Element
+  nsresult CopyInnerTo(mozilla::dom::Element* aDest);
+
+  void GetTitle(mozilla::dom::DOMString& aTitle)
+  {
+    GetHTMLAttr(nsGkAtoms::title, aTitle);
+  }
+  NS_IMETHOD SetTitle(const nsAString& aTitle) override
+  {
+    SetHTMLAttr(nsGkAtoms::title, aTitle);
+    return NS_OK;
+  }
+  void GetLang(mozilla::dom::DOMString& aLang)
+  {
+    GetHTMLAttr(nsGkAtoms::lang, aLang);
+  }
+  NS_IMETHOD SetLang(const nsAString& aLang) override
+  {
+    SetHTMLAttr(nsGkAtoms::lang, aLang);
+    return NS_OK;
+  }
+  void GetDir(mozilla::dom::DOMString& aDir)
+  {
+    GetHTMLEnumAttr(nsGkAtoms::dir, aDir);
+  }
+  void SetDir(const nsAString& aDir, mozilla::ErrorResult& aError)
+  {
+    SetHTMLAttr(nsGkAtoms::dir, aDir, aError);
+  }
+  bool Hidden() const
+  {
+    return GetBoolAttr(nsGkAtoms::hidden);
+  }
+  void SetHidden(bool aHidden, mozilla::ErrorResult& aError)
+  {
+    SetHTMLBoolAttr(nsGkAtoms::hidden, aHidden, aError);
+  }
+  virtual void Click();
+  void GetAccessKey(nsString& aAccessKey)
+  {
+    GetHTMLAttr(nsGkAtoms::accesskey, aAccessKey);
+  }
+  void SetAccessKey(const nsAString& aAccessKey, mozilla::ErrorResult& aError)
+  {
+    SetHTMLAttr(nsGkAtoms::accesskey, aAccessKey, aError);
+  }
+  void GetAccessKeyLabel(nsString& aAccessKeyLabel);
+  virtual bool Draggable() const
+  {
+    return AttrValueIs(kNameSpaceID_None, nsGkAtoms::draggable,
+                       nsGkAtoms::_true, eIgnoreCase);
+  }
+  void SetDraggable(bool aDraggable, mozilla::ErrorResult& aError)
+  {
+    SetHTMLAttr(nsGkAtoms::draggable,
+                aDraggable ? NS_LITERAL_STRING("true")
+                           : NS_LITERAL_STRING("false"),
+                aError);
+  }
+  void GetContentEditable(nsString& aContentEditable)
+  {
+    ContentEditableTristate value = GetContentEditableValue();
+    if (value == eTrue) {
+      aContentEditable.AssignLiteral("true");
+    } else if (value == eFalse) {
+      aContentEditable.AssignLiteral("false");
+    } else {
+      aContentEditable.AssignLiteral("inherit");
+    }
+  }
+  void SetContentEditable(const nsAString& aContentEditable,
+                          mozilla::ErrorResult& aError)
+  {
+    if (aContentEditable.LowerCaseEqualsLiteral("inherit")) {
+      UnsetHTMLAttr(nsGkAtoms::contenteditable, aError);
+    } else if (aContentEditable.LowerCaseEqualsLiteral("true")) {
+      SetHTMLAttr(nsGkAtoms::contenteditable, NS_LITERAL_STRING("true"), aError);
+    } else if (aContentEditable.LowerCaseEqualsLiteral("false")) {
+      SetHTMLAttr(nsGkAtoms::contenteditable, NS_LITERAL_STRING("false"), aError);
+    } else {
+      aError.Throw(NS_ERROR_DOM_SYNTAX_ERR);
+    }
+  }
+  bool IsContentEditable()
+  {
+    for (nsIContent* node = this; node; node = node->GetParent()) {
+      nsGenericHTMLElement* element = FromContent(node);
+      if (element) {
+        ContentEditableTristate value = element->GetContentEditableValue();
+        if (value != eInherit) {
+          return value == eTrue;
+        }
+      }
+    }
+    return false;
+  }
+
+  /**
+   * Returns the count of descendants (inclusive of this node) in
+   * the uncomposed document that are explicitly set as editable.
+   */
+  uint32_t EditableInclusiveDescendantCount();
+
+  mozilla::dom::HTMLMenuElement* GetContextMenu() const;
+  bool Spellcheck();
+  void SetSpellcheck(bool aSpellcheck, mozilla::ErrorResult& aError)
+  {
+    SetHTMLAttr(nsGkAtoms::spellcheck,
+                aSpellcheck ? NS_LITERAL_STRING("true")
+                            : NS_LITERAL_STRING("false"),
+                aError);
+  }
+  bool Scrollgrab() const
+  {
+    return HasFlag(ELEMENT_HAS_SCROLLGRAB);
+  }
+  void SetScrollgrab(bool aValue)
+  {
+    if (aValue) {
+      SetFlags(ELEMENT_HAS_SCROLLGRAB);
+    } else {
+      UnsetFlags(ELEMENT_HAS_SCROLLGRAB);
+    }
+  }
+
+  void GetInnerText(mozilla::dom::DOMString& aValue, mozilla::ErrorResult& aError);
+  void SetInnerText(const nsAString& aValue);
+
+  /**
+   * Determine whether an attribute is an event (onclick, etc.)
+   * @param aName the attribute
+   * @return whether the name is an event handler name
+   */
+  virtual bool IsEventAttributeName(nsIAtom* aName) override;
+
+#define EVENT(name_, id_, type_, struct_) /* nothing; handled by nsINode */
+// The using nsINode::Get/SetOn* are to avoid warnings about shadowing the XPCOM
+// getter and setter on nsINode.
+#define FORWARDED_EVENT(name_, id_, type_, struct_)                           \
+  using nsINode::GetOn##name_;                                                \
+  using nsINode::SetOn##name_;                                                \
+  mozilla::dom::EventHandlerNonNull* GetOn##name_();                          \
+  void SetOn##name_(mozilla::dom::EventHandlerNonNull* handler);
+#define ERROR_EVENT(name_, id_, type_, struct_)                               \
+  using nsINode::GetOn##name_;                                                \
+  using nsINode::SetOn##name_;                                                \
+  already_AddRefed<mozilla::dom::EventHandlerNonNull> GetOn##name_();         \
+  void SetOn##name_(mozilla::dom::EventHandlerNonNull* handler);
+#include "mozilla/EventNameList.h" // IWYU pragma: keep
+#undef ERROR_EVENT
+#undef FORWARDED_EVENT
+#undef EVENT
+  mozilla::dom::Element* GetOffsetParent()
+  {
+    mozilla::CSSIntRect rcFrame;
+    return GetOffsetRect(rcFrame);
+  }
+  int32_t OffsetTop()
+  {
+    mozilla::CSSIntRect rcFrame;
+    GetOffsetRect(rcFrame);
+
+    return rcFrame.y;
+  }
+  int32_t OffsetLeft()
+  {
+    mozilla::CSSIntRect rcFrame;
+    GetOffsetRect(rcFrame);
+
+    return rcFrame.x;
+  }
+  int32_t OffsetWidth()
+  {
+    mozilla::CSSIntRect rcFrame;
+    GetOffsetRect(rcFrame);
+
+    return rcFrame.width;
+  }
+  int32_t OffsetHeight()
+  {
+    mozilla::CSSIntRect rcFrame;
+    GetOffsetRect(rcFrame);
+
+    return rcFrame.height;
+  }
+
+  // These methods are already implemented in nsIContent but we want something
+  // faster for HTMLElements ignoring the namespace checking.
+  // This is safe because we already know that we are in the HTML namespace.
+  inline bool IsHTMLElement() const
+  {
+    return true;
+  }
+
+  inline bool IsHTMLElement(nsIAtom* aTag) const
+  {
+    return mNodeInfo->Equals(aTag);
+  }
+
+  template<typename First, typename... Args>
+  inline bool IsAnyOfHTMLElements(First aFirst, Args... aArgs) const
+  {
+    return IsNodeInternal(aFirst, aArgs...);
+  }
+
+protected:
+  virtual ~nsGenericHTMLElement() {}
+
+public:
+  /**
+   * Get width and height, using given image request if attributes are unset.
+   * Pass a reference to the image request, since the method may change the
+   * value and we want to use the updated value.
+   */
+  nsSize GetWidthHeightForImage(RefPtr<imgRequestProxy>& aImageRequest);
+
+  // XPIDL methods
+  NS_FORWARD_NSIDOMNODE_TO_NSINODE
+
+  NS_FORWARD_NSIDOMELEMENT_TO_GENERIC
+
+  NS_IMETHOD GetTitle(nsAString& aTitle) final override {
+    mozilla::dom::DOMString title;
+    GetTitle(title);
+    title.ToString(aTitle);
+    return NS_OK;
+  }
+  NS_IMETHOD GetLang(nsAString& aLang) final override {
+    mozilla::dom::DOMString lang;
+    GetLang(lang);
+    lang.ToString(aLang);
+    return NS_OK;
+  }
+  NS_IMETHOD GetDir(nsAString& aDir) final override {
+    mozilla::dom::DOMString dir;
+    GetDir(dir);
+    dir.ToString(aDir);
+    return NS_OK;
+  }
+  NS_IMETHOD SetDir(const nsAString& aDir) final override {
+    mozilla::ErrorResult rv;
+    SetDir(aDir, rv);
+    return rv.StealNSResult();
+  }
+  NS_IMETHOD GetDOMClassName(nsAString& aClassName) final {
+    GetHTMLAttr(nsGkAtoms::_class, aClassName);
+    return NS_OK;
+  }
+  NS_IMETHOD SetDOMClassName(const nsAString& aClassName) final {
+    SetClassName(aClassName);
+    return NS_OK;
+  }
+  NS_IMETHOD GetDataset(nsISupports** aDataset) final override;
+  NS_IMETHOD GetHidden(bool* aHidden) final override {
+    *aHidden = Hidden();
+    return NS_OK;
+  }
+  NS_IMETHOD SetHidden(bool aHidden) final override {
+    mozilla::ErrorResult rv;
+    SetHidden(aHidden, rv);
+    return rv.StealNSResult();
+  }
+  NS_IMETHOD DOMBlur() final override {
+    mozilla::ErrorResult rv;
+    Blur(rv);
+    return rv.StealNSResult();
+  }
+  NS_IMETHOD GetAccessKey(nsAString& aAccessKey) final override {
+    nsString accessKey;
+    GetAccessKey(accessKey);
+    aAccessKey.Assign(accessKey);
+    return NS_OK;
+  }
+  NS_IMETHOD SetAccessKey(const nsAString& aAccessKey) final override {
+    mozilla::ErrorResult rv;
+    SetAccessKey(aAccessKey, rv);
+    return rv.StealNSResult();
+  }
+  NS_IMETHOD GetAccessKeyLabel(nsAString& aAccessKeyLabel)
+    final override {
+    nsString accessKeyLabel;
+    GetAccessKeyLabel(accessKeyLabel);
+    aAccessKeyLabel.Assign(accessKeyLabel);
+    return NS_OK;
+  }
+  NS_IMETHOD SetDraggable(bool aDraggable) final override {
+    mozilla::ErrorResult rv;
+    SetDraggable(aDraggable, rv);
+    return rv.StealNSResult();
+  }
+  NS_IMETHOD GetContentEditable(nsAString& aContentEditable)
+    final override {
+    nsString contentEditable;
+    GetContentEditable(contentEditable);
+    aContentEditable.Assign(contentEditable);
+    return NS_OK;
+  }
+  NS_IMETHOD SetContentEditable(const nsAString& aContentEditable)
+    final override {
+    mozilla::ErrorResult rv;
+    SetContentEditable(aContentEditable, rv);
+    return rv.StealNSResult();
+  }
+  NS_IMETHOD GetIsContentEditable(bool* aIsContentEditable)
+    final override {
+    *aIsContentEditable = IsContentEditable();
+    return NS_OK;
+  }
+  NS_IMETHOD GetContextMenu(nsIDOMHTMLMenuElement** aContextMenu)
+    final override;
+  NS_IMETHOD GetSpellcheck(bool* aSpellcheck) final override {
+    *aSpellcheck = Spellcheck();
+    return NS_OK;
+  }
+  NS_IMETHOD SetSpellcheck(bool aSpellcheck) final override {
+    mozilla::ErrorResult rv;
+    SetSpellcheck(aSpellcheck, rv);
+    return rv.StealNSResult();
+  }
+  NS_IMETHOD GetOuterHTML(nsAString& aOuterHTML) final override {
+    mozilla::dom::Element::GetOuterHTML(aOuterHTML);
+    return NS_OK;
+  }
+  NS_IMETHOD SetOuterHTML(const nsAString& aOuterHTML) final override {
+    mozilla::ErrorResult rv;
+    mozilla::dom::Element::SetOuterHTML(aOuterHTML, rv);
+    return rv.StealNSResult();
+  }
+  NS_IMETHOD InsertAdjacentHTML(const nsAString& position,
+                                const nsAString& text) final override;
+  NS_IMETHOD ScrollIntoView(bool top, uint8_t _argc) final override {
+    if (!_argc) {
+      top = true;
+    }
+    mozilla::dom::Element::ScrollIntoView(top);
+    return NS_OK;
+  }
+  NS_IMETHOD GetOffsetParent(nsIDOMElement** aOffsetParent)
+    final override {
+    mozilla::dom::Element* offsetParent = GetOffsetParent();
+    if (!offsetParent) {
+      *aOffsetParent = nullptr;
+      return NS_OK;
+    }
+    return CallQueryInterface(offsetParent, aOffsetParent);
+  }
+  NS_IMETHOD GetOffsetTop(int32_t* aOffsetTop) final override {
+    *aOffsetTop = OffsetTop();
+    return NS_OK;
+  }
+  NS_IMETHOD GetOffsetLeft(int32_t* aOffsetLeft) final override {
+    *aOffsetLeft = OffsetLeft();
+    return NS_OK;
+  }
+  NS_IMETHOD GetOffsetWidth(int32_t* aOffsetWidth) final override {
+    *aOffsetWidth = OffsetWidth();
+    return NS_OK;
+  }
+  NS_IMETHOD GetOffsetHeight(int32_t* aOffsetHeight) final override {
+    *aOffsetHeight = OffsetHeight();
+    return NS_OK;
+  }
+  NS_IMETHOD DOMClick() final override {
+    Click();
+    return NS_OK;
+  }
+  NS_IMETHOD GetTabIndex(int32_t* aTabIndex) final override {
+    *aTabIndex = TabIndex();
+    return NS_OK;
+  }
+  NS_IMETHOD SetTabIndex(int32_t aTabIndex) final override {
+    mozilla::ErrorResult rv;
+    SetTabIndex(aTabIndex, rv);
+    return rv.StealNSResult();
+  }
+  NS_IMETHOD Focus() final override {
+    mozilla::ErrorResult rv;
+    Focus(rv);
+    return rv.StealNSResult();
+  }
+  NS_IMETHOD GetDraggable(bool* aDraggable) final override {
+    *aDraggable = Draggable();
+    return NS_OK;
+  }
+  NS_IMETHOD GetInnerHTML(nsAString& aInnerHTML) override {
+    return mozilla::dom::Element::GetInnerHTML(aInnerHTML);
+  }
+  using mozilla::dom::Element::SetInnerHTML;
+  NS_IMETHOD SetInnerHTML(const nsAString& aInnerHTML) final override {
+    mozilla::ErrorResult rv;
+    SetInnerHTML(aInnerHTML, rv);
+    return rv.StealNSResult();
+  }
+
+  using nsGenericHTMLElementBase::GetOwnerDocument;
+
+  virtual nsIDOMNode* AsDOMNode() override { return this; }
+
+public:
+  // Implementation for nsIContent
+  virtual nsresult BindToTree(nsIDocument* aDocument, nsIContent* aParent,
+                              nsIContent* aBindingParent,
+                              bool aCompileEventHandlers) override;
+  virtual void UnbindFromTree(bool aDeep = true,
+                              bool aNullParent = true) override;
+
+  MOZ_ALWAYS_INLINE // Avoid a crashy hook from Avast 10 Beta
+  nsresult SetAttr(int32_t aNameSpaceID, nsIAtom* aName,
+                   const nsAString& aValue, bool aNotify)
+  {
+    return SetAttr(aNameSpaceID, aName, nullptr, aValue, aNotify);
+  }
+  virtual nsresult SetAttr(int32_t aNameSpaceID, nsIAtom* aName,
+                           nsIAtom* aPrefix, const nsAString& aValue,
+                           bool aNotify) override;
+  virtual nsresult UnsetAttr(int32_t aNameSpaceID, nsIAtom* aName,
+                             bool aNotify) override;
+  virtual bool IsFocusableInternal(int32_t *aTabIndex, bool aWithMouse) override
+  {
+    bool isFocusable = false;
+    IsHTMLFocusable(aWithMouse, &isFocusable, aTabIndex);
+    return isFocusable;
+  }
+  /**
+   * Returns true if a subclass is not allowed to override the value returned
+   * in aIsFocusable.
+   */
+  virtual bool IsHTMLFocusable(bool aWithMouse,
+                               bool *aIsFocusable,
+                               int32_t *aTabIndex);
+  virtual bool PerformAccesskey(bool aKeyCausesActivation,
+                                bool aIsTrustedEvent) override;
+
+  /**
+   * Check if an event for an anchor can be handled
+   * @return true if the event can be handled, false otherwise
+   */
+  bool CheckHandleEventForAnchorsPreconditions(
+         mozilla::EventChainVisitor& aVisitor);
+  nsresult PreHandleEventForAnchors(mozilla::EventChainPreVisitor& aVisitor);
+  nsresult PostHandleEventForAnchors(mozilla::EventChainPostVisitor& aVisitor);
+  bool IsHTMLLink(nsIURI** aURI) const;
+
+  // HTML element methods
+  void Compact() { mAttrsAndChildren.Compact(); }
+
+  virtual void UpdateEditableState(bool aNotify) override;
+
+  virtual mozilla::EventStates IntrinsicState() const override;
+
+  // Helper for setting our editable flag and notifying
+  void DoSetEditableFlag(bool aEditable, bool aNotify) {
+    SetEditableFlag(aEditable);
+    UpdateState(aNotify);
+  }
+
+  virtual bool ParseAttribute(int32_t aNamespaceID,
+                              nsIAtom* aAttribute,
+                              const nsAString& aValue,
+                              nsAttrValue& aResult) override;
+
+  bool ParseBackgroundAttribute(int32_t aNamespaceID,
+                                nsIAtom* aAttribute,
+                                const nsAString& aValue,
+                                nsAttrValue& aResult);
+
+  NS_IMETHOD_(bool) IsAttributeMapped(const nsIAtom* aAttribute) const override;
+  virtual nsMapRuleToAttributesFunc GetAttributeMappingFunction() const override;
+
+  /**
+   * Get the base target for any links within this piece
+   * of content. Generally, this is the document's base target,
+   * but certain content carries a local base for backward
+   * compatibility.
+   *
+   * @param aBaseTarget the base target [OUT]
+   */
+  void GetBaseTarget(nsAString& aBaseTarget) const;
+
+  /**
+   * Get the primary form control frame for this element.  Same as
+   * GetPrimaryFrame(), except it QI's to nsIFormControlFrame.
+   *
+   * @param aFlush whether to flush out frames so that they're up to date.
+   * @return the primary frame as nsIFormControlFrame
+   */
+  nsIFormControlFrame* GetFormControlFrame(bool aFlushFrames);
+
+  //----------------------------------------
+
+  /**
+   * Parse an alignment attribute (top/middle/bottom/baseline)
+   *
+   * @param aString the string to parse
+   * @param aResult the resulting HTMLValue
+   * @return whether the value was parsed
+   */
+  static bool ParseAlignValue(const nsAString& aString,
+                                nsAttrValue& aResult);
+
+  /**
+   * Parse a div align string to value (left/right/center/middle/justify)
+   *
+   * @param aString the string to parse
+   * @param aResult the resulting HTMLValue
+   * @return whether the value was parsed
+   */
+  static bool ParseDivAlignValue(const nsAString& aString,
+                                   nsAttrValue& aResult);
+
+  /**
+   * Convert a table halign string to value (left/right/center/char/justify)
+   *
+   * @param aString the string to parse
+   * @param aResult the resulting HTMLValue
+   * @return whether the value was parsed
+   */
+  static bool ParseTableHAlignValue(const nsAString& aString,
+                                      nsAttrValue& aResult);
+
+  /**
+   * Convert a table cell halign string to value
+   *
+   * @param aString the string to parse
+   * @param aResult the resulting HTMLValue
+   * @return whether the value was parsed
+   */
+  static bool ParseTableCellHAlignValue(const nsAString& aString,
+                                          nsAttrValue& aResult);
+
+  /**
+   * Convert a table valign string to value (left/right/center/char/justify/
+   * abscenter/absmiddle/middle)
+   *
+   * @param aString the string to parse
+   * @param aResult the resulting HTMLValue
+   * @return whether the value was parsed
+   */
+  static bool ParseTableVAlignValue(const nsAString& aString,
+                                      nsAttrValue& aResult);
+
+  /**
+   * Convert an image attribute to value (width, height, hspace, vspace, border)
+   *
+   * @param aAttribute the attribute to parse
+   * @param aString the string to parse
+   * @param aResult the resulting HTMLValue
+   * @return whether the value was parsed
+   */
+  static bool ParseImageAttribute(nsIAtom* aAttribute,
+                                    const nsAString& aString,
+                                    nsAttrValue& aResult);
+
+  static bool ParseReferrerAttribute(const nsAString& aString,
+                                     nsAttrValue& aResult);
+
+  /**
+   * Convert a frameborder string to value (yes/no/1/0)
+   *
+   * @param aString the string to parse
+   * @param aResult the resulting HTMLValue
+   * @return whether the value was parsed
+   */
+  static bool ParseFrameborderValue(const nsAString& aString,
+                                      nsAttrValue& aResult);
+
+  /**
+   * Convert a scrolling string to value (yes/no/on/off/scroll/noscroll/auto)
+   *
+   * @param aString the string to parse
+   * @param aResult the resulting HTMLValue
+   * @return whether the value was parsed
+   */
+  static bool ParseScrollingValue(const nsAString& aString,
+                                    nsAttrValue& aResult);
+
+  /*
+   * Attribute Mapping Helpers
+   */
+
+  /**
+   * A style attribute mapping function for the most common attributes, to be
+   * called by subclasses' attribute mapping functions.  Currently handles
+   * dir, lang and hidden, could handle others.
+   *
+   * @param aAttributes the list of attributes to map
+   * @param aData the returned rule data [INOUT]
+   * @see GetAttributeMappingFunction
+   */
+  static void MapCommonAttributesInto(const nsMappedAttributes* aAttributes, 
+                                      nsRuleData* aRuleData);
+  /**
+   * Same as MapCommonAttributesInto except that it does not handle hidden.
+   *
+   * @param aAttributes the list of attributes to map
+   * @param aData the returned rule data [INOUT]
+   * @see GetAttributeMappingFunction
+   */
+  static void MapCommonAttributesIntoExceptHidden(const nsMappedAttributes* aAttributes,
+                                                  nsRuleData* aRuleData);
+
+  static const MappedAttributeEntry sCommonAttributeMap[];
+  static const MappedAttributeEntry sImageMarginSizeAttributeMap[];
+  static const MappedAttributeEntry sImageBorderAttributeMap[];
+  static const MappedAttributeEntry sImageAlignAttributeMap[];
+  static const MappedAttributeEntry sDivAlignAttributeMap[];
+  static const MappedAttributeEntry sBackgroundAttributeMap[];
+  static const MappedAttributeEntry sBackgroundColorAttributeMap[];
+  
+  /**
+   * Helper to map the align attribute into a style struct.
+   *
+   * @param aAttributes the list of attributes to map
+   * @param aData the returned rule data [INOUT]
+   * @see GetAttributeMappingFunction
+   */
+  static void MapImageAlignAttributeInto(const nsMappedAttributes* aAttributes,
+                                         nsRuleData* aData);
+
+  /**
+   * Helper to map the align attribute into a style struct for things
+   * like <div>, <h1>, etc.
+   *
+   * @param aAttributes the list of attributes to map
+   * @param aData the returned rule data [INOUT]
+   * @see GetAttributeMappingFunction
+   */
+  static void MapDivAlignAttributeInto(const nsMappedAttributes* aAttributes,
+                                       nsRuleData* aData);
+
+  /**
+   * Helper to map the image border attribute into a style struct.
+   *
+   * @param aAttributes the list of attributes to map
+   * @param aData the returned rule data [INOUT]
+   * @see GetAttributeMappingFunction
+   */
+  static void MapImageBorderAttributeInto(const nsMappedAttributes* aAttributes,
+                                          nsRuleData* aData);
+  /**
+   * Helper to map the image margin attribute into a style struct.
+   *
+   * @param aAttributes the list of attributes to map
+   * @param aData the returned rule data [INOUT]
+   * @see GetAttributeMappingFunction
+   */
+  static void MapImageMarginAttributeInto(const nsMappedAttributes* aAttributes,
+                                          nsRuleData* aData);
+  /**
+   * Helper to map the image position attribute into a style struct.
+   *
+   * @param aAttributes the list of attributes to map
+   * @param aData the returned rule data [INOUT]
+   * @see GetAttributeMappingFunction
+   */
+  static void MapImageSizeAttributesInto(const nsMappedAttributes* aAttributes,
+                                         nsRuleData* aData);
+  /**
+   * Helper to map the background attribute
+   * into a style struct.
+   *
+   * @param aAttributes the list of attributes to map
+   * @param aData the returned rule data [INOUT]
+   * @see GetAttributeMappingFunction
+   */
+  static void MapBackgroundInto(const nsMappedAttributes* aAttributes,
+                                nsRuleData* aData);
+  /**
+   * Helper to map the bgcolor attribute
+   * into a style struct.
+   *
+   * @param aAttributes the list of attributes to map
+   * @param aData the returned rule data [INOUT]
+   * @see GetAttributeMappingFunction
+   */
+  static void MapBGColorInto(const nsMappedAttributes* aAttributes,
+                             nsRuleData* aData);
+  /**
+   * Helper to map the background attributes (currently background and bgcolor)
+   * into a style struct.
+   *
+   * @param aAttributes the list of attributes to map
+   * @param aData the returned rule data [INOUT]
+   * @see GetAttributeMappingFunction
+   */
+  static void MapBackgroundAttributesInto(const nsMappedAttributes* aAttributes,
+                                          nsRuleData* aData);
+  /**
+   * Helper to map the scrolling attribute on FRAME and IFRAME
+   * into a style struct.
+   *
+   * @param aAttributes the list of attributes to map
+   * @param aData the returned rule data [INOUT]
+   * @see GetAttributeMappingFunction
+   */
+  static void MapScrollingAttributeInto(const nsMappedAttributes* aAttributes,
+                                        nsRuleData* aData);
+  /**
+   * Get the presentation context for this content node.
+   * @return the presentation context
+   */
+  enum PresContextFor
+  {
+    eForComposedDoc,
+    eForUncomposedDoc
+  };
+  nsPresContext* GetPresContext(PresContextFor aFor);
+
+  // Form Helper Routines
+  /**
+   * Find an ancestor of this content node which is a form (could be null)
+   * @param aCurrentForm the current form for this node.  If this is
+   *        non-null, and no ancestor form is found, and the current form is in
+   *        a connected subtree with the node, the current form will be
+   *        returned.  This is needed to handle cases when HTML elements have a
+   *        current form that they're not descendants of.
+   * @note This method should not be called if the element has a form attribute.
+   */
+  mozilla::dom::HTMLFormElement*
+  FindAncestorForm(mozilla::dom::HTMLFormElement* aCurrentForm = nullptr);
+
+  virtual void RecompileScriptEventListeners() override;
+
+  /**
+   * See if the document being tested has nav-quirks mode enabled.
+   * @param doc the document
+   */
+  static bool InNavQuirksMode(nsIDocument* aDoc);
+
+  /**
+   * Locate an nsIEditor rooted at this content node, if there is one.
+   */
+  nsresult GetEditor(nsIEditor** aEditor);
+
+  /**
+   * Helper method for NS_IMPL_URI_ATTR macro.
+   * Gets the absolute URI value of an attribute, by resolving any relative
+   * URIs in the attribute against the baseuri of the element. If the attribute
+   * isn't a relative URI the value of the attribute is returned as is. Only
+   * works for attributes in null namespace.
+   *
+   * @param aAttr      name of attribute.
+   * @param aBaseAttr  name of base attribute.
+   * @param aResult    result value [out]
+   */
+  void GetURIAttr(nsIAtom* aAttr, nsIAtom* aBaseAttr, nsAString& aResult) const;
+
+  /**
+   * Gets the absolute URI values of an attribute, by resolving any relative
+   * URIs in the attribute against the baseuri of the element. If a substring
+   * isn't a relative URI, the substring is returned as is. Only works for
+   * attributes in null namespace.
+   */
+  bool GetURIAttr(nsIAtom* aAttr, nsIAtom* aBaseAttr, nsIURI** aURI) const;
+
+  /**
+   * Returns the current disabled state of the element.
+   */
+  virtual bool IsDisabled() const {
+    return false;
+  }
+
+  bool IsHidden() const
+  {
+    return HasAttr(kNameSpaceID_None, nsGkAtoms::hidden);
+  }
+
+  virtual bool IsLabelable() const override;
+  virtual bool IsInteractiveHTMLContent(bool aIgnoreTabindex) const override;
+
+  static bool TouchEventsEnabled(JSContext* /* unused */, JSObject* /* unused */);
+
+  static inline bool
+  CanHaveName(nsIAtom* aTag)
+  {
+    return aTag == nsGkAtoms::img ||
+           aTag == nsGkAtoms::form ||
+           aTag == nsGkAtoms::applet ||
+           aTag == nsGkAtoms::embed ||
+           aTag == nsGkAtoms::object;
+  }
+  static inline bool
+  ShouldExposeNameAsHTMLDocumentProperty(Element* aElement)
+  {
+    return aElement->IsHTMLElement() &&
+           CanHaveName(aElement->NodeInfo()->NameAtom());
+  }
+  static inline bool
+  ShouldExposeIdAsHTMLDocumentProperty(Element* aElement)
+  {
+    if (aElement->IsAnyOfHTMLElements(nsGkAtoms::applet,
+                                      nsGkAtoms::embed,
+                                      nsGkAtoms::object)) {
+      return true;
+    }
+
+    // Per spec, <img> is exposed by id only if it also has a nonempty
+    // name (which doesn't have to match the id or anything).
+    // HasName() is true precisely when name is nonempty.
+    return aElement->IsHTMLElement(nsGkAtoms::img) && aElement->HasName();
+  }
+
+  static bool
+  IsScrollGrabAllowed(JSContext*, JSObject*);
+
+protected:
+  /**
+   * Add/remove this element to the documents name cache
+   */
+  void AddToNameTable(nsIAtom* aName) {
+    NS_ASSERTION(HasName(), "Node doesn't have name?");
+    nsIDocument* doc = GetUncomposedDoc();
+    if (doc && !IsInAnonymousSubtree()) {
+      doc->AddToNameTable(this, aName);
+    }
+  }
+  void RemoveFromNameTable() {
+    if (HasName()) {
+      nsIDocument* doc = GetUncomposedDoc();
+      if (doc) {
+        doc->RemoveFromNameTable(this, GetParsedAttr(nsGkAtoms::name)->
+                                         GetAtomValue());
+      }
+    }
+  }
+
+  /**
+   * Register or unregister an access key to this element based on the
+   * accesskey attribute.
+   */
+  void RegAccessKey()
+  {
+    if (HasFlag(NODE_HAS_ACCESSKEY)) {
+      RegUnRegAccessKey(true);
+    }
+  }
+
+  void UnregAccessKey()
+  {
+    if (HasFlag(NODE_HAS_ACCESSKEY)) {
+      RegUnRegAccessKey(false);
+    }
+  }
+
+private:
+  void RegUnRegAccessKey(bool aDoReg);
+
+protected:
+  virtual nsresult AfterSetAttr(int32_t aNamespaceID, nsIAtom* aName,
+                                const nsAttrValue* aValue, bool aNotify) override;
+
+  virtual mozilla::EventListenerManager*
+    GetEventListenerManagerForAttr(nsIAtom* aAttrName,
+                                   bool* aDefer) override;
+
+  /**
+   * Dispatch a simulated mouse click by keyboard to the given element.
+   */
+  nsresult DispatchSimulatedClick(nsGenericHTMLElement* aElement,
+                                  bool aIsTrusted,
+                                  nsPresContext* aPresContext);
+
+  /**
+   * Create a URI for the given aURISpec string.
+   * Returns INVALID_STATE_ERR and nulls *aURI if aURISpec is empty
+   * and the document's URI matches the element's base URI.
+   */
+  nsresult NewURIFromString(const nsAString& aURISpec, nsIURI** aURI);
+
+  void GetHTMLAttr(nsIAtom* aName, nsAString& aResult) const
+  {
+    GetAttr(kNameSpaceID_None, aName, aResult);
+  }
+  void GetHTMLAttr(nsIAtom* aName, mozilla::dom::DOMString& aResult) const
+  {
+    GetAttr(kNameSpaceID_None, aName, aResult);
+  }
+  void GetHTMLEnumAttr(nsIAtom* aName, nsAString& aResult) const
+  {
+    GetEnumAttr(aName, nullptr, aResult);
+  }
+  void GetHTMLURIAttr(nsIAtom* aName, nsAString& aResult) const
+  {
+    GetURIAttr(aName, nullptr, aResult);
+  }
+
+  void SetHTMLAttr(nsIAtom* aName, const nsAString& aValue)
+  {
+    SetAttr(kNameSpaceID_None, aName, aValue, true);
+  }
+  void SetHTMLAttr(nsIAtom* aName, const nsAString& aValue, mozilla::ErrorResult& aError)
+  {
+    mozilla::dom::Element::SetAttr(aName, aValue, aError);
+  }
+  void UnsetHTMLAttr(nsIAtom* aName, mozilla::ErrorResult& aError)
+  {
+    mozilla::dom::Element::UnsetAttr(aName, aError);
+  }
+  void SetHTMLBoolAttr(nsIAtom* aName, bool aValue, mozilla::ErrorResult& aError)
+  {
+    if (aValue) {
+      SetHTMLAttr(aName, EmptyString(), aError);
+    } else {
+      UnsetHTMLAttr(aName, aError);
+    }
+  }
+  template<typename T>
+  void SetHTMLIntAttr(nsIAtom* aName, T aValue, mozilla::ErrorResult& aError)
+  {
+    nsAutoString value;
+    value.AppendInt(aValue);
+
+    SetHTMLAttr(aName, value, aError);
+  }
+
+  /**
+   * Helper method for NS_IMPL_STRING_ATTR macro.
+   * Sets the value of an attribute, returns specified default value if the
+   * attribute isn't set. Only works for attributes in null namespace.
+   *
+   * @param aAttr    name of attribute.
+   * @param aDefault default-value to return if attribute isn't set.
+   * @param aResult  result value [out]
+   */
+  nsresult SetAttrHelper(nsIAtom* aAttr, const nsAString& aValue);
+
+  /**
+   * Helper method for NS_IMPL_INT_ATTR macro.
+   * Gets the integer-value of an attribute, returns specified default value
+   * if the attribute isn't set or isn't set to an integer. Only works for
+   * attributes in null namespace.
+   *
+   * @param aAttr    name of attribute.
+   * @param aDefault default-value to return if attribute isn't set.
+   */
+  int32_t GetIntAttr(nsIAtom* aAttr, int32_t aDefault) const;
+
+  /**
+   * Helper method for NS_IMPL_INT_ATTR macro.
+   * Sets value of attribute to specified integer. Only works for attributes
+   * in null namespace.
+   *
+   * @param aAttr    name of attribute.
+   * @param aValue   Integer value of attribute.
+   */
+  nsresult SetIntAttr(nsIAtom* aAttr, int32_t aValue);
+
+  /**
+   * Helper method for NS_IMPL_UINT_ATTR macro.
+   * Gets the unsigned integer-value of an attribute, returns specified default
+   * value if the attribute isn't set or isn't set to an integer. Only works for
+   * attributes in null namespace.
+   *
+   * @param aAttr    name of attribute.
+   * @param aDefault default-value to return if attribute isn't set.
+   */
+  uint32_t GetUnsignedIntAttr(nsIAtom* aAttr, uint32_t aDefault) const;
+
+  /**
+   * Helper method for NS_IMPL_UINT_ATTR macro.
+   * Sets value of attribute to specified unsigned integer. Only works for
+   * attributes in null namespace.
+   *
+   * @param aAttr    name of attribute.
+   * @param aValue   Integer value of attribute.
+   * @param aDefault Default value (in case value is out of range).  If the spec
+   *                 doesn't provide one, should be 1 if the value is limited to
+   *                 nonzero values, and 0 otherwise.
+   */
+  void SetUnsignedIntAttr(nsIAtom* aName, uint32_t aValue, uint32_t aDefault,
+                          mozilla::ErrorResult& aError)
+  {
+    nsAutoString value;
+    if (aValue > INT32_MAX) {
+      value.AppendInt(aDefault);
+    } else {
+      value.AppendInt(aValue);
+    }
+
+    SetHTMLAttr(aName, value, aError);
+  }
+
+  /**
+   * Sets value of attribute to specified double. Only works for attributes
+   * in null namespace.
+   *
+   * @param aAttr    name of attribute.
+   * @param aValue   Double value of attribute.
+   */
+  void SetDoubleAttr(nsIAtom* aAttr, double aValue, mozilla::ErrorResult& aRv)
+  {
+    nsAutoString value;
+    value.AppendFloat(aValue);
+
+    SetHTMLAttr(aAttr, value, aRv);
+  }
+
+  /**
+   * Locates the nsIEditor associated with this node.  In general this is
+   * equivalent to GetEditorInternal(), but for designmode or contenteditable,
+   * this may need to get an editor that's not actually on this element's
+   * associated TextControlFrame.  This is used by the spellchecking routines
+   * to get the editor affected by changing the spellcheck attribute on this
+   * node.
+   */
+  virtual already_AddRefed<nsIEditor> GetAssociatedEditor();
+
+  /**
+   * Get the frame's offset information for offsetTop/Left/Width/Height.
+   * Returns the parent the offset is relative to.
+   * @note This method flushes pending notifications (Flush_Layout).
+   * @param aRect the offset information [OUT]
+   */
+  mozilla::dom::Element* GetOffsetRect(mozilla::CSSIntRect& aRect);
+
+  /**
+   * Returns true if this is the current document's body element
+   */
+  bool IsCurrentBodyElement();
+
+  /**
+   * Ensures all editors associated with a subtree are synced, for purposes of
+   * spellchecking.
+   */
+  static void SyncEditorsOnSubtree(nsIContent* content);
+
+  enum ContentEditableTristate {
+    eInherit = -1,
+    eFalse = 0,
+    eTrue = 1
+  };
+
+  /**
+   * Returns eTrue if the element has a contentEditable attribute and its value
+   * is "true" or an empty string. Returns eFalse if the element has a
+   * contentEditable attribute and its value is "false". Otherwise returns
+   * eInherit.
+   */
+  ContentEditableTristate GetContentEditableValue() const
+  {
+    static const nsIContent::AttrValuesArray values[] =
+      { &nsGkAtoms::_false, &nsGkAtoms::_true, &nsGkAtoms::_empty, nullptr };
+
+    if (!MayHaveContentEditableAttr())
+      return eInherit;
+
+    int32_t value = FindAttrValueIn(kNameSpaceID_None,
+                                    nsGkAtoms::contenteditable, values,
+                                    eIgnoreCase);
+
+    return value > 0 ? eTrue : (value == 0 ? eFalse : eInherit);
+  }
+
+  // Used by A, AREA, LINK, and STYLE.
+  already_AddRefed<nsIURI> GetHrefURIForAnchors() const;
+
+  /**
+   * Returns whether this element is an editable root. There are two types of
+   * editable roots:
+   *   1) the documentElement if the whole document is editable (for example for
+   *      desginMode=on)
+   *   2) an element that is marked editable with contentEditable=true and that
+   *      doesn't have a parent or whose parent is not editable.
+   * Note that this doesn't return input and textarea elements that haven't been
+   * made editable through contentEditable or designMode.
+   */
+  bool IsEditableRoot() const;
+
+private:
+  void ChangeEditableState(int32_t aChange);
+};
+
+namespace mozilla {
+namespace dom {
+class HTMLFieldSetElement;
+} // namespace dom
+} // namespace mozilla
+
+#define FORM_ELEMENT_FLAG_BIT(n_) NODE_FLAG_BIT(ELEMENT_TYPE_SPECIFIC_BITS_OFFSET + (n_))
+
+// Form element specific bits
+enum {
+  // If this flag is set on an nsGenericHTMLFormElement or an HTMLImageElement,
+  // that means that we have added ourselves to our mForm.  It's possible to
+  // have a non-null mForm, but not have this flag set.  That happens when the
+  // form is set via the content sink.
+  ADDED_TO_FORM =                         FORM_ELEMENT_FLAG_BIT(0),
+
+  // If this flag is set on an nsGenericHTMLFormElement or an HTMLImageElement,
+  // that means that its form is in the process of being unbound from the tree,
+  // and this form element hasn't re-found its form in
+  // nsGenericHTMLFormElement::UnbindFromTree yet.
+  MAYBE_ORPHAN_FORM_ELEMENT =             FORM_ELEMENT_FLAG_BIT(1)
+};
+
+// NOTE: I don't think it's possible to have the above two flags set at the
+// same time, so if it becomes an issue we can probably merge them into the
+// same bit.  --bz
+
+ASSERT_NODE_FLAGS_SPACE(ELEMENT_TYPE_SPECIFIC_BITS_OFFSET + 2);
+
+#undef FORM_ELEMENT_FLAG_BIT
+
+/**
+ * A helper class for form elements that can contain children
+ */
+class nsGenericHTMLFormElement : public nsGenericHTMLElement,
+                                 public nsIFormControl
+{
+public:
+  explicit nsGenericHTMLFormElement(already_AddRefed<mozilla::dom::NodeInfo>& aNodeInfo);
+
+  NS_DECL_ISUPPORTS_INHERITED
+
+  nsINode* GetScopeChainParent() const override;
+
+  virtual bool IsNodeOfType(uint32_t aFlags) const override;
+  virtual void SaveSubtreeState() override;
+
+  // nsIFormControl
+  virtual mozilla::dom::HTMLFieldSetElement* GetFieldSet() override;
+  virtual mozilla::dom::Element* GetFormElement() override;
+  mozilla::dom::HTMLFormElement* GetForm() const
+  {
+    return mForm;
+  }
+  virtual void SetForm(nsIDOMHTMLFormElement* aForm) override;
+  virtual void ClearForm(bool aRemoveFromForm) override;
+
+  nsresult GetForm(nsIDOMHTMLFormElement** aForm);
+
+  NS_IMETHOD SaveState() override
+  {
+    return NS_OK;
+  }
+
+  virtual bool RestoreState(nsPresState* aState) override
+  {
+    return false;
+  }
+  virtual bool AllowDrop() override
+  {
+    return true;
+  }
+
+  // nsIContent
+  virtual nsresult BindToTree(nsIDocument* aDocument, nsIContent* aParent,
+                              nsIContent* aBindingParent,
+                              bool aCompileEventHandlers) override;
+  virtual void UnbindFromTree(bool aDeep = true,
+                              bool aNullParent = true) override;
+  virtual IMEState GetDesiredIMEState() override;
+  virtual mozilla::EventStates IntrinsicState() const override;
+
+  virtual nsresult PreHandleEvent(
+                     mozilla::EventChainPreVisitor& aVisitor) override;
+
+  virtual bool IsDisabled() const override;
+
+  /**
+   * This callback is called by a fieldest on all its elements whenever its
+   * disabled attribute is changed so the element knows its disabled state
+   * might have changed.
+   *
+   * @note Classes redefining this method should not do any content
+   * state updates themselves but should just make sure to call into
+   * nsGenericHTMLFormElement::FieldSetDisabledChanged.
+   */
+  virtual void FieldSetDisabledChanged(bool aNotify);
+
+  void FieldSetFirstLegendChanged(bool aNotify) {
+    UpdateFieldSet(aNotify);
+  }
+
+  /**
+   * This callback is called by a fieldset on all it's elements when it's being
+   * destroyed. When called, the elements should check that aFieldset is there
+   * first parent fieldset and null mFieldset in that case only.
+   *
+   * @param aFieldSet The fieldset being removed.
+   */
+  void ForgetFieldSet(nsIContent* aFieldset);
+
+  /**
+   * Returns if the control can be disabled.
+   */
+  bool CanBeDisabled() const;
+
+  virtual bool IsHTMLFocusable(bool aWithMouse, bool* aIsFocusable,
+                                 int32_t* aTabIndex) override;
+
+  virtual bool IsLabelable() const override;
+
+protected:
+  virtual ~nsGenericHTMLFormElement();
+
+  virtual nsresult BeforeSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
+                                 nsAttrValueOrString* aValue,
+                                 bool aNotify) override;
+
+  virtual nsresult AfterSetAttr(int32_t aNameSpaceID, nsIAtom* aName,
+                                const nsAttrValue* aValue, bool aNotify) override;
+
+  /**
+   * This method will update the form owner, using @form or looking to a parent.
+   *
+   * @param aBindToTree Whether the element is being attached to the tree.
+   * @param aFormIdElement The element associated with the id in @form. If
+   * aBindToTree is false, aFormIdElement *must* contain the element associated
+   * with the id in @form. Otherwise, it *must* be null.
+   *
+   * @note Callers of UpdateFormOwner have to be sure the element is in a
+   * document (GetUncomposedDoc() != nullptr).
+   */
+  void UpdateFormOwner(bool aBindToTree, Element* aFormIdElement);
+
+  /**
+   * This method will update mFieldset and set it to the first fieldset parent.
+   */
+  void UpdateFieldSet(bool aNotify);
+
+  /**
+   * Add a form id observer which will observe when the element with the id in
+   * @form will change.
+   *
+   * @return The element associated with the current id in @form (may be null).
+   */
+  Element* AddFormIdObserver();
+
+  /**
+   * Remove the form id observer.
+   */
+  void RemoveFormIdObserver();
+
+  /**
+   * This method is a a callback for IDTargetObserver (from nsIDocument).
+   * It will be called each time the element associated with the id in @form
+   * changes.
+   */
+  static bool FormIdUpdated(Element* aOldElement, Element* aNewElement,
+                              void* aData);
+
+  // Returns true if the event should not be handled from PreHandleEvent
+  bool IsElementDisabledForEvents(mozilla::EventMessage aMessage,
+                                  nsIFrame* aFrame);
+
+  // The focusability state of this form control.  eUnfocusable means that it
+  // shouldn't be focused at all, eInactiveWindow means it's in an inactive
+  // window, eActiveWindow means it's in an active window.
+  enum FocusTristate {
+    eUnfocusable,
+    eInactiveWindow,
+    eActiveWindow
+  };
+
+  // Get our focus state.  If this returns eInactiveWindow, it will set this
+  // element as the focused element for that window.
+  FocusTristate FocusState();
+
+  /** The form that contains this control */
+  mozilla::dom::HTMLFormElement* mForm;
+
+  /* This is a pointer to our closest fieldset parent if any */
+  mozilla::dom::HTMLFieldSetElement* mFieldSet;
+};
+
+class nsGenericHTMLFormElementWithState : public nsGenericHTMLFormElement
+{
+public:
+  explicit nsGenericHTMLFormElementWithState(already_AddRefed<mozilla::dom::NodeInfo>& aNodeInfo);
+
+  /**
+   * Get the presentation state for a piece of content, or create it if it does
+   * not exist.  Generally used by SaveState().
+   */
+  nsPresState* GetPrimaryPresState();
+
+  /**
+   * Get the layout history object for a particular piece of content.
+   *
+   * @param aRead if true, won't return a layout history state if the
+   *              layout history state is empty.
+   * @return the history state object
+   */
+  already_AddRefed<nsILayoutHistoryState>
+    GetLayoutHistory(bool aRead);
+
+  /**
+   * Restore the state for a form control.  Ends up calling
+   * nsIFormControl::RestoreState().
+   *
+   * @return false if RestoreState() was not called, the return
+   *         value of RestoreState() otherwise.
+   */
+  bool RestoreFormControlState();
+
+  /**
+   * Called when we have been cloned and adopted, and the information of the
+   * node has been changed.
+   */
+  virtual void NodeInfoChanged() override;
+
+protected:
+  /* Generates the state key for saving the form state in the session if not
+     computed already. The result is stored in mStateKey on success */
+  nsresult GenerateStateKey();
+
+  /* Used to store the key to that element in the session. Is void until
+     GenerateStateKey has been used */
+  nsCString mStateKey;
+};
+
+//----------------------------------------------------------------------
+
+/**
+ * This macro is similar to NS_IMPL_STRING_ATTR except that the getter method
+ * falls back to an alternative method if the content attribute isn't set.
+ */
+#define NS_IMPL_STRING_ATTR_WITH_FALLBACK(_class, _method, _atom, _fallback) \
+  NS_IMETHODIMP                                                              \
+  _class::Get##_method(nsAString& aValue)                                    \
+  {                                                                          \
+    if (!GetAttr(kNameSpaceID_None, nsGkAtoms::_atom, aValue)) {             \
+      _fallback(aValue);                                                     \
+    }                                                                        \
+    return NS_OK;                                                            \
+  }                                                                          \
+  NS_IMETHODIMP                                                              \
+  _class::Set##_method(const nsAString& aValue)                              \
+  {                                                                          \
+    return SetAttrHelper(nsGkAtoms::_atom, aValue);                          \
+  }
+
+/**
+ * A macro to implement the getter and setter for a given integer
+ * valued content property. The method uses the generic GetAttr and
+ * SetAttr methods.
+ */
+#define NS_IMPL_INT_ATTR(_class, _method, _atom)                    \
+  NS_IMPL_INT_ATTR_DEFAULT_VALUE(_class, _method, _atom, 0)
+
+#define NS_IMPL_INT_ATTR_DEFAULT_VALUE(_class, _method, _atom, _default)  \
+  NS_IMETHODIMP                                                           \
+  _class::Get##_method(int32_t* aValue)                                   \
+  {                                                                       \
+    *aValue = GetIntAttr(nsGkAtoms::_atom, _default);                     \
+    return NS_OK;                                                         \
+  }                                                                       \
+  NS_IMETHODIMP                                                           \
+  _class::Set##_method(int32_t aValue)                                    \
+  {                                                                       \
+    return SetIntAttr(nsGkAtoms::_atom, aValue);                          \
+  }
+
+/**
+ * A macro to implement the getter and setter for a given unsigned integer
+ * valued content property. The method uses GetUnsignedIntAttr and
+ * SetUnsignedIntAttr methods.
+ */
+#define NS_IMPL_UINT_ATTR(_class, _method, _atom)                         \
+  NS_IMPL_UINT_ATTR_DEFAULT_VALUE(_class, _method, _atom, 0)
+
+#define NS_IMPL_UINT_ATTR_DEFAULT_VALUE(_class, _method, _atom, _default) \
+  NS_IMETHODIMP                                                           \
+  _class::Get##_method(uint32_t* aValue)                                  \
+  {                                                                       \
+    *aValue = GetUnsignedIntAttr(nsGkAtoms::_atom, _default);             \
+    return NS_OK;                                                         \
+  }                                                                       \
+  NS_IMETHODIMP                                                           \
+  _class::Set##_method(uint32_t aValue)                                   \
+  {                                                                       \
+    mozilla::ErrorResult rv;                                              \
+    SetUnsignedIntAttr(nsGkAtoms::_atom, aValue, _default, rv);           \
+    return rv.StealNSResult();                                            \
+  }
+
+/**
+ * A macro to implement the getter and setter for a given unsigned integer
+ * valued content property. The method uses GetUnsignedIntAttr and
+ * SetUnsignedIntAttr methods. This macro is similar to NS_IMPL_UINT_ATTR except
+ * that it throws an exception if the set value is null.
+ */
+#define NS_IMPL_UINT_ATTR_NON_ZERO(_class, _method, _atom)                \
+  NS_IMPL_UINT_ATTR_NON_ZERO_DEFAULT_VALUE(_class, _method, _atom, 1)
+
+#define NS_IMPL_UINT_ATTR_NON_ZERO_DEFAULT_VALUE(_class, _method, _atom, _default) \
+  NS_IMETHODIMP                                                           \
+  _class::Get##_method(uint32_t* aValue)                                  \
+  {                                                                       \
+    *aValue = GetUnsignedIntAttr(nsGkAtoms::_atom, _default);             \
+    return NS_OK;                                                         \
+  }                                                                       \
+  NS_IMETHODIMP                                                           \
+  _class::Set##_method(uint32_t aValue)                                   \
+  {                                                                       \
+    if (aValue == 0) {                                                    \
+      return NS_ERROR_DOM_INDEX_SIZE_ERR;                                 \
+    }                                                                     \
+    mozilla::ErrorResult rv;                                              \
+    SetUnsignedIntAttr(nsGkAtoms::_atom, aValue, _default, rv);           \
+    return rv.StealNSResult();                                            \
+  }
+
+/**
+ * A macro to implement the getter and setter for a given content
+ * property that needs to return a URI in string form.  The method
+ * uses the generic GetAttr and SetAttr methods.  This macro is much
+ * like the NS_IMPL_STRING_ATTR macro, except we make sure the URI is
+ * absolute.
+ */
+#define NS_IMPL_URI_ATTR(_class, _method, _atom)                    \
+  NS_IMETHODIMP                                                     \
+  _class::Get##_method(nsAString& aValue)                           \
+  {                                                                 \
+    GetURIAttr(nsGkAtoms::_atom, nullptr, aValue);                  \
+    return NS_OK;                                                   \
+  }                                                                 \
+  NS_IMETHODIMP                                                     \
+  _class::Set##_method(const nsAString& aValue)                     \
+  {                                                                 \
+    return SetAttrHelper(nsGkAtoms::_atom, aValue);               \
+  }
+
+#define NS_IMPL_URI_ATTR_WITH_BASE(_class, _method, _atom, _base_atom)       \
+  NS_IMETHODIMP                                                              \
+  _class::Get##_method(nsAString& aValue)                                    \
+  {                                                                          \
+    GetURIAttr(nsGkAtoms::_atom, nsGkAtoms::_base_atom, aValue);             \
+    return NS_OK;                                                            \
+  }                                                                          \
+  NS_IMETHODIMP                                                              \
+  _class::Set##_method(const nsAString& aValue)                              \
+  {                                                                          \
+    return SetAttrHelper(nsGkAtoms::_atom, aValue);                        \
+  }
+
+/**
+ * A macro to implement getter and setter for action and form action content
+ * attributes. It's very similar to NS_IMPL_URI_ATTR excepted that if the
+ * content attribute is the empty string, the empty string is returned.
+ */
+#define NS_IMPL_ACTION_ATTR(_class, _method, _atom)                 \
+  NS_IMETHODIMP                                                     \
+  _class::Get##_method(nsAString& aValue)                           \
+  {                                                                 \
+    GetAttr(kNameSpaceID_None, nsGkAtoms::_atom, aValue);           \
+    if (!aValue.IsEmpty()) {                                        \
+      GetURIAttr(nsGkAtoms::_atom, nullptr, aValue);                 \
+    }                                                               \
+    return NS_OK;                                                   \
+  }                                                                 \
+  NS_IMETHODIMP                                                     \
+  _class::Set##_method(const nsAString& aValue)                     \
+  {                                                                 \
+    return SetAttrHelper(nsGkAtoms::_atom, aValue);                 \
+  }
+
+/**
+ * A macro to implement the getter and setter for a given content
+ * property that needs to set a non-negative integer. The method
+ * uses the generic GetAttr and SetAttr methods. This macro is much
+ * like the NS_IMPL_INT_ATTR macro except we throw an exception if
+ * the set value is negative.
+ */
+#define NS_IMPL_NON_NEGATIVE_INT_ATTR(_class, _method, _atom)             \
+  NS_IMPL_NON_NEGATIVE_INT_ATTR_DEFAULT_VALUE(_class, _method, _atom, -1)
+
+#define NS_IMPL_NON_NEGATIVE_INT_ATTR_DEFAULT_VALUE(_class, _method, _atom, _default)  \
+  NS_IMETHODIMP                                                           \
+  _class::Get##_method(int32_t* aValue)                                   \
+  {                                                                       \
+    *aValue = GetIntAttr(nsGkAtoms::_atom, _default);                     \
+    return NS_OK;                                                         \
+  }                                                                       \
+  NS_IMETHODIMP                                                           \
+  _class::Set##_method(int32_t aValue)                                    \
+  {                                                                       \
+    if (aValue < 0) {                                                     \
+      return NS_ERROR_DOM_INDEX_SIZE_ERR;                                 \
+    }                                                                     \
+    return SetIntAttr(nsGkAtoms::_atom, aValue);                          \
+  }
+
+/**
+ * A macro to implement the getter and setter for a given content
+ * property that needs to set an enumerated string. The method
+ * uses a specific GetEnumAttr and the generic SetAttrHelper methods.
+ */
+#define NS_IMPL_ENUM_ATTR_DEFAULT_VALUE(_class, _method, _atom, _default) \
+  NS_IMETHODIMP                                                           \
+  _class::Get##_method(nsAString& aValue)                                 \
+  {                                                                       \
+    GetEnumAttr(nsGkAtoms::_atom, _default, aValue);                      \
+    return NS_OK;                                                         \
+  }                                                                       \
+  NS_IMETHODIMP                                                           \
+  _class::Set##_method(const nsAString& aValue)                           \
+  {                                                                       \
+    return SetAttrHelper(nsGkAtoms::_atom, aValue);                       \
+  }
+
+/**
+ * A macro to implement the getter and setter for a given content
+ * property that needs to set an enumerated string that has different
+ * default values for missing and invalid values. The method uses a
+ * specific GetEnumAttr and the generic SetAttrHelper methods.
+ */
+#define NS_IMPL_ENUM_ATTR_DEFAULT_MISSING_INVALID_VALUES(_class, _method, _atom, _defaultMissing, _defaultInvalid) \
+  NS_IMETHODIMP                                                                                   \
+  _class::Get##_method(nsAString& aValue)                                                         \
+  {                                                                                               \
+    GetEnumAttr(nsGkAtoms::_atom, _defaultMissing, _defaultInvalid, aValue);                      \
+    return NS_OK;                                                                                 \
+  }                                                                                               \
+  NS_IMETHODIMP                                                                                   \
+  _class::Set##_method(const nsAString& aValue)                                                   \
+  {                                                                                               \
+    return SetAttrHelper(nsGkAtoms::_atom, aValue);                                               \
+  }
+
+#define NS_INTERFACE_MAP_ENTRY_IF_TAG(_interface, _tag)                       \
+  NS_INTERFACE_MAP_ENTRY_CONDITIONAL(_interface,                              \
+                                     mNodeInfo->Equals(nsGkAtoms::_tag))
+
+
+/**
+ * A macro to declare the NS_NewHTMLXXXElement() functions.
+ */
+#define NS_DECLARE_NS_NEW_HTML_ELEMENT(_elementName)                       \
+namespace mozilla {                                                        \
+namespace dom {                                                            \
+class HTML##_elementName##Element;                                         \
+}                                                                          \
+}                                                                          \
+nsGenericHTMLElement*                                                      \
+NS_NewHTML##_elementName##Element(already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo, \
+                                  mozilla::dom::FromParser aFromParser = mozilla::dom::NOT_FROM_PARSER);
+
+#define NS_DECLARE_NS_NEW_HTML_ELEMENT_AS_SHARED(_elementName)             \
+inline nsGenericHTMLElement*                                               \
+NS_NewHTML##_elementName##Element(already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo, \
+                                  mozilla::dom::FromParser aFromParser = mozilla::dom::NOT_FROM_PARSER) \
+{                                                                          \
+  return NS_NewHTMLSharedElement(mozilla::Move(aNodeInfo), aFromParser);   \
+}
+
+/**
+ * A macro to implement the NS_NewHTMLXXXElement() functions.
+ */
+#define NS_IMPL_NS_NEW_HTML_ELEMENT(_elementName)                            \
+nsGenericHTMLElement*                                                        \
+NS_NewHTML##_elementName##Element(already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo, \
+                                  mozilla::dom::FromParser aFromParser)      \
+{                                                                            \
+  return new mozilla::dom::HTML##_elementName##Element(aNodeInfo);           \
+}
+
+#define NS_IMPL_NS_NEW_HTML_ELEMENT_CHECK_PARSER(_elementName)               \
+nsGenericHTMLElement*                                                        \
+NS_NewHTML##_elementName##Element(already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo, \
+                                  mozilla::dom::FromParser aFromParser)      \
+{                                                                            \
+  return new mozilla::dom::HTML##_elementName##Element(aNodeInfo,            \
+                                                       aFromParser);         \
+}
+
+// Here, we expand 'NS_DECLARE_NS_NEW_HTML_ELEMENT()' by hand.
+// (Calling the macro directly (with no args) produces compiler warnings.)
+nsGenericHTMLElement*
+NS_NewHTMLElement(already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo,
+                  mozilla::dom::FromParser aFromParser = mozilla::dom::NOT_FROM_PARSER);
+
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Shared)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(SharedList)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(SharedObject)
+
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Anchor)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Area)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Audio)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(BR)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Body)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Button)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Canvas)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Content)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Mod)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Data)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(DataList)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Details)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Div)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(FieldSet)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Font)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Form)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Frame)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(FrameSet)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(HR)
+NS_DECLARE_NS_NEW_HTML_ELEMENT_AS_SHARED(Head)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Heading)
+NS_DECLARE_NS_NEW_HTML_ELEMENT_AS_SHARED(Html)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(IFrame)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Image)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Input)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(LI)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Label)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Legend)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Link)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Map)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Menu)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(MenuItem)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Meta)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Meter)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Object)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(OptGroup)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Option)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Output)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Paragraph)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Picture)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Pre)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Progress)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Script)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Select)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Shadow)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Source)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Span)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Style)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Summary)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(TableCaption)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(TableCell)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(TableCol)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Table)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(TableRow)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(TableSection)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Tbody)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Template)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(TextArea)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Tfoot)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Thead)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Time)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Title)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Track)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Unknown)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Video)
+
+inline nsISupports*
+ToSupports(nsGenericHTMLElement* aHTMLElement)
+{
+  return static_cast<nsIContent*>(aHTMLElement);
+}
+
+inline nsISupports*
+ToCanonicalSupports(nsGenericHTMLElement* aHTMLElement)
+{
+  return static_cast<nsIContent*>(aHTMLElement);
+}
+
+#endif /* nsGenericHTMLElement_h___ */