Add m-esr52 at 52.6.0

1 files changed, 738 insertions, 0 deletions

diff --git a/dom/webidl/InputMethod.webidl b/dom/webidl/InputMethod.webidl
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+/* -*- Mode: IDL; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* 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/.
+ */
+
+/**
+ * InputMethod API implements a bridge between the web content hosting an input
+ * element and the input content (a.k.a. input app, virtual keyboard app,
+ * or IME). This API is input content facing in order for it to interact with
+ * the remote input element.
+ * The API also contains a few Gaia System app only methods
+ * (marked with "input-manage" permission) for Gaia System app to interact with
+ * some types of inputs and to regulate the input apps.
+ */
+[JSImplementation="@mozilla.org/b2g-inputmethod;1",
+ NavigatorProperty="mozInputMethod",
+ Pref="dom.mozInputMethod.enabled",
+ ChromeOnly]
+interface MozInputMethod : EventTarget {
+  /**
+   * Activate or decactive current API instance.
+   * Gaia System app call this method via BrowserElement#setInputMethodActive.
+   */
+  [ChromeOnly]
+  void setActive(boolean isActive);
+
+  /**
+   * InputMethodManager contain a few global methods expose to input apps.
+   */
+  readonly attribute MozInputMethodManager mgmt;
+
+  /**
+   * Fired when the input context changes, include changes from and to null.
+   * The new InputContext instance will be available in the event
+   * object under |inputcontext| property.  When it changes to null it
+   * means the app (the user of this API) no longer has the control of
+   * the original focused input field.
+   * Note that if the app saves the original context, it might get
+   * void; implementation decides when to void the input context.
+   */
+  attribute EventHandler oninputcontextchange;
+
+  /**
+   * An "input context" is mapped to a text field that the app is
+   * allow to mutate. This attribute should be null when there is no
+   * text field currently focused.
+   */
+  readonly attribute MozInputContext? inputcontext;
+
+  /**
+   * Add a dynamically declared input.
+   *
+   * The id must not be the same with any statically declared input in the app
+   * manifest. If an input of the same id is already declared, the info of that
+   * input will be updated.
+   */
+  Promise<void> addInput(DOMString inputId,
+                         MozInputMethodInputManifest inputManifest);
+
+  /**
+   * Remove a dynamically declared input.
+   *
+   * The id must not be the same with any statically declared input in the app
+   * manifest. Silently resolves if the input is not previously declared;
+   * rejects if attempt to remove a statically declared input.
+   */
+  Promise<void> removeInput(DOMString id);
+
+  /**
+   * Remove focus from the current input, usable by Gaia System app, globally,
+   * regardless of the current focus state.
+   */
+  void removeFocus();
+
+  /**
+   * The following are internal methods for Firefox OS System app only,
+   * for handling the "option" group inputs.
+   */
+
+  /**
+   * Set the value on the currently focused element. This has to be used
+   * for special situations where the value had to be chosen amongst a
+   * list (type=month) or a widget (type=date, time, etc.).
+   * If the value passed in parameter isn't valid (in the term of HTML5
+   * Forms Validation), the value will simply be ignored by the element.
+   */
+  void setValue(DOMString value);
+
+  /**
+   * Select the <select> option specified by index.
+   * If this method is called on a <select> that support multiple
+   * selection, then the option specified by index will be added to
+   * the selection.
+   * If this method is called for a select that does not support multiple
+   * selection the previous element will be unselected.
+   */
+  void setSelectedOption(long index);
+
+  /**
+   * Select the <select> options specified by indexes. All other options
+   * will be deselected.
+   * If this method is called for a <select> that does not support multiple
+   * selection, then the last index specified in indexes will be selected.
+   */
+  void setSelectedOptions(sequence<long> indexes);
+};
+
+/**
+ * InputMethodManager contains a few of the global methods for the input app.
+ */
+[JSImplementation="@mozilla.org/b2g-imm;1",
+ Pref="dom.mozInputMethod.enabled",
+ ChromeOnly]
+interface MozInputMethodManager : EventTarget {
+  /**
+   * Ask the OS to show a list of available inputs for users to switch from.
+   * OS should sliently ignore this request if the app is currently not the
+   * active one.
+   */
+  void showAll();
+
+  /**
+   * Ask the OS to switch away from the current active input app.
+   * OS should sliently ignore this request if the app is currently not the
+   * active one.
+   */
+  void next();
+
+  /**
+   * If this method returns true, it is recommended that the input app provides
+   * a shortcut that would invoke the next() method above, for easy switching
+   * between inputs -- i.e. show a "global" button on screen if the input app
+   * implements an on-screen virtual keyboard.
+   *
+   * The returning value is depend on the inputType of the current input context.
+   */
+  boolean supportsSwitching();
+
+  /**
+   * Ask the OS to remove the input focus, will cause the lost of input context.
+   * OS should sliently ignore this request if the app is currently not the
+   * active one.
+   */
+  void hide();
+
+  /**
+   * Update Gecko with information on the input types which supportsSwitching()
+   * should return ture.
+   *
+   * @param types Array of input types in which supportsSwitching() should
+   *              return true.
+   */
+  void setSupportsSwitchingTypes(sequence<MozInputMethodInputContextInputTypes> types);
+
+  /**
+   * CustomEvent dispatches to System when there is an input to handle.
+   * If the API consumer failed to handle and call preventDefault(),
+   * there will be a message printed on the console.
+   *
+   * evt.detail is defined by MozInputContextFocusEventDetail.
+   */
+  attribute EventHandler oninputcontextfocus;
+
+  /**
+   * Event dispatches to System when there is no longer an input to handle.
+   * If the API consumer failed to handle and call preventDefault(),
+   * there will be a message printed on the console.
+   */
+  attribute EventHandler oninputcontextblur;
+
+  /**
+   * Event dispatches to System when there is a showAll() call.
+   * If the API consumer failed to handle and call preventDefault(),
+   * there will be a message printed on the console.
+   */
+  attribute EventHandler onshowallrequest;
+
+  /**
+   * Event dispatches to System when there is a next() call.
+   * If the API consumer failed to handle and call preventDefault(),
+   * there will be a message printed on the console.
+   */
+  attribute EventHandler onnextrequest;
+
+  /**
+   * Event dispatches to System when there is a addInput() call.
+   * The API consumer must call preventDefault() to indicate the event is
+   * consumed, otherwise the request is not considered handled even if
+   * waitUntil() was called.
+   *
+   * evt.detail is defined by MozInputRegistryEventDetail.
+   */
+  attribute EventHandler onaddinputrequest;
+
+  /**
+   * Event dispatches to System when there is a removeInput() call.
+   * The API consumer must call preventDefault() to indicate the event is
+   * consumed, otherwise the request is not considered handled even if
+   * waitUntil() was called.
+   *
+   * evt.detail is defined by MozInputRegistryEventDetail.
+   */
+  attribute EventHandler onremoveinputrequest;
+};
+
+/**
+ * Detail of the inputcontextfocus event.
+ */
+[JSImplementation="@mozilla.org/b2g-imm-focus;1",
+ Pref="dom.mozInputMethod.enabled",
+ ChromeOnly]
+interface MozInputContextFocusEventDetail {
+  /**
+   * The type of the focused input.
+   */
+  readonly attribute MozInputMethodInputContextTypes type;
+  /**
+   * The input type of the focused input.
+   */
+  readonly attribute MozInputMethodInputContextInputTypes inputType;
+
+  /**
+   * The following is only needed for rendering and handling "option" input types,
+   * in System app.
+   */
+
+  /**
+   * Current value of the input.
+   */
+  readonly attribute DOMString? value;
+  /**
+   * An object representing all the <optgroup> and <option> elements
+   * in the <select> element.
+   */
+  [Pure, Cached, Frozen]
+  readonly attribute MozInputContextChoicesInfo? choices;
+  /**
+   * Max/min value of <input>
+   */
+  readonly attribute DOMString? min;
+  readonly attribute DOMString? max;
+};
+
+/**
+ * Information about the options within the <select> element.
+ */
+dictionary MozInputContextChoicesInfo {
+  boolean multiple;
+  sequence<MozInputMethodChoiceDict> choices;
+};
+
+/**
+ * Content of the option header (<optgroup>) or an option (<option>).
+ */
+dictionary MozInputMethodChoiceDict {
+  boolean group;
+  DOMString text;
+  boolean disabled;
+  boolean? inGroup;
+  boolean? selected;
+  long? optionIndex;
+};
+
+/**
+ * detail of addinputrequest or removeinputrequest event.
+ */
+[JSImplementation="@mozilla.org/b2g-imm-input-registry;1",
+ Pref="dom.mozInputMethod.enabled",
+ ChromeOnly]
+interface MozInputRegistryEventDetail {
+  /**
+   * Manifest URL of the requesting app.
+   */
+  readonly attribute DOMString manifestURL;
+  /**
+   * ID of the input
+   */
+  readonly attribute DOMString inputId;
+  /**
+   * Input manifest of the input to add.
+   * Null for removeinputrequest event.
+   */
+  [Pure, Cached, Frozen]
+  readonly attribute MozInputMethodInputManifest? inputManifest;
+  /**
+   * Resolve or Reject the addInput() or removeInput() call when the passed
+   * promises are resolved.
+   */
+  [Throws]
+  void waitUntil(Promise<any> p);
+};
+
+/**
+ * The input context, which consists of attributes and information of current
+ * input field. It also hosts the methods available to the keyboard app to
+ * mutate the input field represented. An "input context" gets void when the
+ * app is no longer allowed to interact with the text field,
+ * e.g., the text field does no longer exist, the app is being switched to
+ * background, and etc.
+ */
+[JSImplementation="@mozilla.org/b2g-inputcontext;1",
+ Pref="dom.mozInputMethod.enabled",
+ ChromeOnly]
+interface MozInputContext: EventTarget {
+  /**
+   * Type of the InputContext. See MozInputMethodInputContextTypes
+   */
+  readonly attribute MozInputMethodInputContextTypes? type;
+
+  /**
+   * InputType of the InputContext. See MozInputMethodInputContextInputTypes.
+   */
+  readonly attribute MozInputMethodInputContextInputTypes? inputType;
+
+  /**
+   * The inputmode string, representing the inputmode of the input.
+   * See http://www.whatwg.org/specs/web-apps/current-work/multipage/association-of-controls-and-forms.html#input-modalities:-the-inputmode-attribute
+   */
+  readonly attribute DOMString? inputMode;
+
+  /**
+   * The primary language for the input field.
+   * It is the value of HTMLElement.lang.
+   * See http://www.whatwg.org/specs/web-apps/current-work/multipage/elements.html#htmlelement
+   */
+  readonly attribute DOMString? lang;
+
+  /**
+   * Get the whole text content of the input field.
+   * @return DOMString
+   */
+  Promise<DOMString> getText(optional long offset, optional long length);
+
+  /**
+   * The start and stop position of the current selection.
+   */
+  readonly attribute long selectionStart;
+  readonly attribute long selectionEnd;
+
+  /**
+   * The text in the current input.
+   */
+  readonly attribute DOMString? text;
+
+  /**
+   * The text before and after the begining of the selected text.
+   *
+   * You should use the text property instead because these properties are
+   * truncated at 100 characters.
+   */
+  readonly attribute DOMString? textBeforeCursor;
+  readonly attribute DOMString? textAfterCursor;
+
+  /**
+   * Set the selection range of the the editable text.
+   * Note: This method cannot be used to move the cursor during composition. Calling this
+   * method will cancel composition.
+   * @param start The beginning of the selected text.
+   * @param length The length of the selected text.
+   *
+   * Note that the start position should be less or equal to the end position.
+   * To move the cursor, set the start and end position to the same value.
+   *
+   * @return boolean
+   */
+  Promise<boolean> setSelectionRange(long start, long length);
+
+  /* User moves the cursor, or changes the selection with other means. If the text around
+   * cursor has changed, but the cursor has not been moved, the IME won't get notification.
+   *
+   * evt.detail is defined by MozInputContextSelectionChangeEventDetail.
+   */
+  attribute EventHandler onselectionchange;
+
+  /**
+   * Commit text to current input field and replace text around
+   * cursor position. It will clear the current composition.
+   *
+   * @param text The string to be replaced with.
+   * @param offset The offset from the cursor position where replacing starts. Defaults to 0.
+   * @param length The length of text to replace. Defaults to 0.
+   * @return boolean
+   */
+  Promise<boolean> replaceSurroundingText(DOMString text, optional long offset, optional long length);
+
+  /**
+   * Delete text around the cursor.
+   * @param offset The offset from the cursor position where deletion starts.
+   * @param length The length of text to delete.
+   * TODO: maybe updateSurroundingText(DOMString beforeText, DOMString afterText); ?
+   * @return boolean
+   */
+  Promise<boolean> deleteSurroundingText(long offset, long length);
+
+  /**
+   * Notifies when the text around the cursor is changed, due to either text
+   * editing or cursor movement. If the cursor has been moved, but the text around has not
+   * changed, the IME won't get notification.
+   *
+   * evt.detail is defined by MozInputContextSurroundingTextChangeEventDetail.
+   */
+  attribute EventHandler onsurroundingtextchange;
+
+  /**
+   * Send a string/character with its key events. There are two ways of invocating
+   * the method for backward compability purpose.
+   *
+   * (1) The recommended way, allow specifying DOM level 3 properties like |code|.
+   * @param dictOrKeyCode See MozInputMethodKeyboardEventDict.
+   * @param charCode disregarded
+   * @param modifiers disregarded
+   * @param repeat disregarded
+   *
+   * (2) Deprecated, reserved for backward compability.
+   * @param dictOrKeyCode keyCode of the key to send, should be one of the DOM_VK_ value in KeyboardEvent.
+   * @param charCode charCode of the character, should be 0 for non-printable keys.
+   * @param modifiers this paramater is no longer honored.
+   * @param repeat indicates whether a key would be sent repeatedly.
+   *
+   * @return A promise. Resolve to true if succeeds.
+   *                    Rejects to a string indicating the error.
+   *
+   * Note that, if you want to send a key n times repeatedly, make sure set
+   * parameter repeat to true and invoke sendKey n times, and invoke keyup
+   * after the end of the input.
+   */
+  Promise<boolean> sendKey((MozInputMethodRequiredKeyboardEventDict or long) dictOrKeyCode,
+                           optional long charCode,
+                           optional long modifiers,
+                           optional boolean repeat);
+
+  /**
+   * Send a string/character with keydown, and keypress events.
+   * keyup should be called afterwards to ensure properly sequence.
+   *
+   * @param dict See MozInputMethodKeyboardEventDict.
+   *
+   * @return A promise. Resolve to true if succeeds.
+   *                    Rejects to a string indicating the error.
+   */
+  Promise<boolean> keydown(MozInputMethodRequiredKeyboardEventDict dict);
+
+  /**
+   * Send a keyup event. keydown should be called first to ensure properly sequence.
+   *
+   * @param dict See MozInputMethodKeyboardEventDict.
+   *
+   * @return A promise. Resolve to true if succeeds.
+   *                    Rejects to a string indicating the error.
+   */
+  Promise<boolean> keyup(MozInputMethodRequiredKeyboardEventDict dict);
+
+  /**
+   * Set current composing text. This method will start composition or update
+   * composition if it has started. The composition will be started right
+   * before the cursor position and any selected text will be replaced by the
+   * composing text. When the composition is started, calling this method can
+   * update the text and move cursor winthin the range of the composing text.
+   * @param text The new composition text to show.
+   * @param cursor The new cursor position relative to the start of the
+   * composition text. The cursor should be positioned within the composition
+   * text. This means the value should be >= 0 and <= the length of
+   * composition text. Defaults to the lenght of composition text, i.e., the
+   * cursor will be positioned after the composition text.
+   * @param clauses The array of composition clause information. If not set,
+   * only one clause is supported.
+   * @param dict The properties of the keyboard event that cause the composition
+   * to set. keydown or keyup event will be fired if it's necessary.
+   * For compatibility, we recommend that you should always set this argument
+   * if it's caused by a key operation.
+   *
+   * The composing text, which is shown with underlined style to distinguish
+   * from the existing text, is used to compose non-ASCII characters from
+   * keystrokes, e.g. Pinyin or Hiragana. The composing text is the
+   * intermediate text to help input complex character and is not committed to
+   * current input field. Therefore if any text operation other than
+   * composition is performed, the composition will automatically end. Same
+   * apply when the inputContext is lost during an unfinished composition
+   * session.
+   *
+   * To finish composition and commit text to current input field, an IME
+   * should call |endComposition|.
+   */
+  Promise<boolean> setComposition(DOMString text,
+                                  optional long cursor,
+                                  optional sequence<CompositionClauseParameters> clauses,
+                                  optional MozInputMethodKeyboardEventDict dict);
+
+  /**
+   * End composition, clear the composing text and commit given text to
+   * current input field. The text will be committed before the cursor
+   * position.
+   * @param text The text to commited before cursor position. If empty string
+   * is given, no text will be committed.
+   * @param dict The properties of the keyboard event that cause the composition
+   * to end. keydown or keyup event will be fired if it's necessary.
+   * For compatibility, we recommend that you should always set this argument
+   * if it's caused by a key operation.
+   *
+   * Note that composition always ends automatically with nothing to commit if
+   * the composition does not explicitly end by calling |endComposition|, but
+   * is interrupted by |sendKey|, |setSelectionRange|,
+   * |replaceSurroundingText|, |deleteSurroundingText|, user moving the
+   * cursor, changing the focus, etc.
+   */
+  Promise<boolean> endComposition(optional DOMString text,
+                                  optional MozInputMethodKeyboardEventDict dict);
+
+  /**
+   * The interface used to receive the native events from hardware keyboard
+   */
+  readonly attribute MozHardwareInput? hardwareinput;
+};
+
+/*
+ * This interface will be added into inputcontext and used to receive the
+ * events from the hardware keyboard.
+ * Example:
+ *   mozInputMethod.inputcontext.hardwareinput.addEventListener('keyup', this);
+ *   mozInputMethod.inputcontext.hardwareinput.removeEventListener('keyup', this);
+ */
+[JSImplementation="@mozilla.org/b2g-hardwareinput;1",
+ Pref="dom.mozInputMethod.enabled",
+ ChromeOnly]
+interface MozHardwareInput: EventTarget {
+};
+
+/**
+ * Detail of the selectionchange event.
+ */
+[JSImplementation="@mozilla.org/b2g-imm-selectionchange;1",
+ Pref="dom.mozInputMethod.enabled",
+ ChromeOnly]
+interface MozInputContextSelectionChangeEventDetail {
+  /**
+   * Indicate whether or not the change is due to our own action from,
+   * for example, sendKey() call.
+   *
+   * Note: this property is untrustworthy because it would still be true even
+   * if script in the page changed the text synchronously upon responding to
+   * events trigger by the call.
+   */
+  readonly attribute boolean ownAction;
+
+  /**
+   * The start and stop position of the current selection.
+   */
+  readonly attribute long selectionStart;
+  readonly attribute long selectionEnd;
+};
+
+/**
+ * Detail of the surroundingtextchange event.
+ */
+[JSImplementation="@mozilla.org/b2g-imm-surroundingtextchange;1",
+ Pref="dom.mozInputMethod.enabled",
+ ChromeOnly]
+interface MozInputContextSurroundingTextChangeEventDetail {
+  /**
+   * Indicate whether or not the change is due to our own action from,
+   * for example, sendKey() call.
+   *
+   * Note: this property is untrustworthy because it would still be true even
+   * if script in the page changed the text synchronously upon responding to
+   * events trigger by the call.
+   */
+  readonly attribute boolean ownAction;
+
+  /**
+   * The text in the current input.
+   */
+  readonly attribute DOMString? text;
+
+  /**
+   * The text before and after the begining of the selected text.
+   *
+   * You should use the text property instead because these properties are
+   * truncated at 100 characters.
+   */
+  readonly attribute DOMString? textBeforeCursor;
+  readonly attribute DOMString? textAfterCursor;
+};
+
+enum CompositionClauseSelectionType {
+  "raw-input",
+  "selected-raw-text",
+  "converted-text",
+  "selected-converted-text"
+};
+
+dictionary CompositionClauseParameters {
+  CompositionClauseSelectionType selectionType = "raw-input";
+  long length;
+};
+
+/**
+ * Types are HTML tag names of the inputs that is explosed with InputContext,
+ * *and* the special keyword "contenteditable" for contenteditable element.
+ */
+enum MozInputMethodInputContextTypes {
+  "input", "textarea", "contenteditable",
+  /**
+   * <select> is managed by the API but it is handled by the System app only,
+   * so this value is only accessible by System app from inputcontextfocus event.
+   */
+  "select"
+};
+
+/**
+ * InputTypes of the input that InputContext is representing. The value
+ * is inferred from the type attribute of element.
+ *
+ * See https://html.spec.whatwg.org/multipage/forms.html#states-of-the-type-attribute
+ * for types of HTMLInputElement.
+ *
+ * They are divided into groups -- an layout/input capable of handling one type
+ * in the group is considered as capable of handling all of the types in the
+ * same group.
+ * The layout/input that could handle type "text" is considered as the fallback
+ * if none of layout/input installed can handle a specific type.
+ *
+ * Groups and fallbacks is enforced in Gaia System app currently.
+ *
+ * Noted that the actual virtual keyboard to show, for example in the case of
+ * Gaia Keyboard app, will also depend on the inputMode of the input element.
+ */
+enum MozInputMethodInputContextInputTypes {
+  /**
+   * Group "text". Be reminded that contenteditable element is assigned with
+   * an input type of "textarea".
+   */
+  "text", "search", "textarea",
+  /**
+   * Group "number"
+   */
+  "number", "tel",
+  /**
+   * Group "url"
+   */
+  "url",
+  /**
+   * Group "email"
+   */
+  "email",
+  /**
+   * Group "password".
+   * An non-Latin alphabet layout/input should not be able to handle this type.
+   */
+  "password",
+  /**
+   * Group "option". These types are handled by System app itself currently, so
+   * no input app will be set to active for these input types.
+   * System app access these types from inputcontextfocus event.
+   * ("select-one" and "select-multiple" are valid HTMLSelectElement#type.)
+   */
+  "datetime", "date", "month", "week", "time", "datetime-local", "color",
+  "select-one", "select-multiple"
+  /**
+   * These types are ignored by the API even though they are valid
+   * HTMLInputElement#type.
+   */
+  //"checkbox", "radio", "file", "submit", "image", "range", "reset", "button"
+};
+
+/**
+ * An input app can host multiple inputs (a.k.a. layouts) and the capability of
+ * the input is described by the input manifest.
+ */
+dictionary MozInputMethodInputManifest {
+  required DOMString launch_path;
+  required DOMString name;
+  DOMString? description;
+  sequence<MozInputMethodInputContextInputTypes> types;
+};
+
+/**
+ * A MozInputMethodKeyboardEventDictBase contains the following properties,
+ * indicating the properties of the keyboard event caused.
+ *
+ * This is the base dictionary type for us to create two child types that could
+ * be used as argument type in two types of methods, as WebIDL parser required.
+ *
+ */
+dictionary MozInputMethodKeyboardEventDictBase {
+  /**
+   * String/character to output, or a registered name of non-printable key.
+   * (To be defined in the inheriting dictionary types.)
+   */
+  // DOMString key;
+  /**
+   * String/char indicating the virtual hardware key pressed. Optional.
+   * Must be a value defined in
+   * http://www.w3.org/TR/DOM-Level-3-Events-code/#keyboard-chording-virtual
+   * If your keyboard app emulates physical keyboard layout, this value should
+   * not be empty string. Otherwise, it should be empty string.
+   */
+  DOMString code = "";
+  /**
+   * keyCode of the keyboard event. Optional.
+   * To be disregarded if |key| is an alphanumeric character.
+   * If the key causes inputting a character and if your keyboard app emulates
+   * a physical keyboard layout, this value should be same as the value used
+   * by Firefox for desktop. If the key causes inputting an ASCII character
+   * but if your keyboard app doesn't emulate any physical keyboard layouts,
+   * the value should be proper value for the key value.
+   */
+  long? keyCode;
+  /**
+   * Indicates whether a key would be sent repeatedly. Optional.
+   */
+  boolean repeat = false;
+  /**
+   * Optional. True if |key| property is explicitly referring to a printable key.
+   * When this is set, key will be printable even if the |key| value matches any
+   * of the registered name of non-printable keys.
+   */
+  boolean printable = false;
+};
+
+/**
+ * For methods like setComposition() and endComposition(), the optional
+ * dictionary type argument is really optional when all of it's property
+ * are optional.
+ * This dictionary type is used to denote that argument.
+ */
+dictionary MozInputMethodKeyboardEventDict : MozInputMethodKeyboardEventDictBase {
+  DOMString? key;
+};
+
+/**
+ * For methods like keydown() and keyup(), the dictionary type argument is
+ * considered required only if at least one of it's property is required.
+ * This dictionary type is used to denote that argument.
+ */
+dictionary MozInputMethodRequiredKeyboardEventDict : MozInputMethodKeyboardEventDictBase {
+  required DOMString key;
+};