Update the rest of SwitchAccess to ES2015

Bug: 884297
Change-Id: Iff20201277983eed3d851279ed6e7042ae17d250
Reviewed-on: https://chromium-review.googlesource.com/1237554
Commit-Queue: Zach Helfinstein <zhelfins@chromium.org>
Reviewed-by: David Tseng <dtseng@chromium.org>
Cr-Commit-Position: refs/heads/master@{#593271}

chrome/browser/resources/chromeos/switch_access/context_menu_manager.js

@@ -5,88 +5,59 @@
 /**
  * Class to handle interactions with the context menu, including moving through
  * and selecting actions.
- *
- * @constructor
- * @param {!AutomationManager} automationManager
- * @param {!chrome.automation.AutomationNode} desktop
  */
-function ContextMenuManager(automationManager, desktop) {
-  /**
-   * A list of the ContextMenu actions that are currently enabled.
-   * @private {!Array<ContextMenuManager.Action>}
-   */
-  this.actions_ = [];
-
-  /**
-   * The parent automation manager.
-   * @private {!AutomationManager}
-   */
-  this.automationManager_ = automationManager;
-
-  /**
-   * The root node of the screen.
-   * @private {!chrome.automation.AutomationNode}
-   */
-  this.desktop_ = desktop;
-
-  /**
-   * The root node of the context menu.
-   * @private {chrome.automation.AutomationNode}
-   */
-  this.menuNode_;
 
-  /**
-   * The current node of the context menu.
-   * @private {chrome.automation.AutomationNode}
-   */
-  this.node_;
-
-  /**
-   * Keeps track of when we're in the context menu.
-   * @private {boolean}
-   */
-  this.inContextMenu_ = false;
-
-  this.init_();
-}
-
-/**
- * Actions available in the Context Menu.
- * @enum {string}
- * @const
- */
-ContextMenuManager.Action = {
-  CLICK: 'click',
-  OPTIONS: 'options',
-  SCROLL_BACKWARD: 'scroll-backward',
-  SCROLL_DOWN: 'scroll-down',
-  SCROLL_FORWARD: 'scroll-forward',
-  SCROLL_LEFT: 'scroll-left',
-  SCROLL_RIGHT: 'scroll-right',
-  SCROLL_UP: 'scroll-up'
-};
-
-/**
- * The ID for the div containing the context menu.
- * @const
- */
-ContextMenuManager.MenuId = 'switchaccess_contextmenu_actions';
+class ContextMenuManager {
+  /**
+   * @param {!AutomationManager} automationManager
+   * @param {!chrome.automation.AutomationNode} desktop
+   */
+  constructor(automationManager, desktop) {
+    /**
+     * A list of the ContextMenu actions that are currently enabled.
+     * @private {!Array<ContextMenuManager.Action>}
+     */
+    this.actions_ = [];
+
+    /**
+     * The parent automation manager.
+     * @private {!AutomationManager}
+     */
+    this.automationManager_ = automationManager;
+
+    /**
+     * The root node of the screen.
+     * @private {!chrome.automation.AutomationNode}
+     */
+    this.desktop_ = desktop;
+
+    /**
+     * The root node of the context menu.
+     * @private {chrome.automation.AutomationNode}
+     */
+    this.menuNode_;
+
+    /**
+     * The current node of the context menu.
+     * @private {chrome.automation.AutomationNode}
+     */
+    this.node_;
+
+    /**
+     * Keeps track of when we're in the context menu.
+     * @private {boolean}
+     */
+    this.inContextMenu_ = false;
 
-ContextMenuManager.prototype = {
-  /**
-   * @private
-   */
-  init_: function() {
-    // Listen for messages from the menu.
-    window.addEventListener('message', this.onMessageReceived_.bind(this));
-  },
+    this.init_();
+  }
 
   /**
    * Enter the context menu and highlight the first available action.
    *
    * @param {!Array<!ContextMenuManager.Action>} actions
    */
-  enter: function(actions) {
+  enter(actions) {
     this.inContextMenu_ = true;
     if (actions !== this.actions_) {
       this.actions_ = actions;
@@ -96,51 +67,51 @@ ContextMenuManager.prototype = {
 
     this.node_ = this.menuNode();
     this.moveForward();
-  },
+  }
 
   /**
    * Exits the context menu.
    */
-  exit: function() {
+  exit() {
     this.clearFocusRing_();
     this.inContextMenu_ = false;
     if (this.node_)
       this.node_ = null;
-  },
+  }
 
   /**
    * Move to the next available action in the menu. If this is no next action,
    * select the whole context menu to loop again.
    * @return {boolean} Whether this function had any effect.
    */
-  moveForward: function() {
+  moveForward() {
     if (!this.node_ || !this.inContextMenu_)
       return false;
 
     this.clearFocusRing_();
-    let treeWalker = new AutomationTreeWalker(
+    const treeWalker = new AutomationTreeWalker(
         this.node_, constants.Dir.FORWARD,
         SwitchAccessPredicate.restrictions(this.menuNode()));
-    let node = treeWalker.next().node;
+    const node = treeWalker.next().node;
     if (!node)
       this.node_ = this.menuNode();
     else
       this.node_ = node;
     this.updateFocusRing_();
     return true;
-  },
+  }
 
   /**
    * Move to the previous available action in the context menu. If we're at the
    * beginning of the list, start again at the end.
    * @return {boolean} Whether this function had any effect.
    */
-  moveBackward: function() {
+  moveBackward() {
     if (!this.node_ || !this.inContextMenu_)
       return false;
 
     this.clearFocusRing_();
-    let treeWalker = new AutomationTreeWalker(
+    const treeWalker = new AutomationTreeWalker(
         this.node_, constants.Dir.BACKWARD,
         SwitchAccessPredicate.restrictions(this.menuNode()));
     let node = treeWalker.next().node;
@@ -159,7 +130,7 @@ ContextMenuManager.prototype = {
     this.node_ = node;
     this.updateFocusRing_();
     return true;
-  },
+  }
 
   /**
    * Perform the action indicated by the current button (or no action if the
@@ -167,7 +138,7 @@ ContextMenuManager.prototype = {
    * traditional navigation.
    * @return {boolean} Whether this function had any effect.
    */
-  selectCurrentNode: function() {
+  selectCurrentNode() {
     if (!this.node_ || !this.inContextMenu_)
       return false;
 
@@ -175,42 +146,50 @@ ContextMenuManager.prototype = {
     this.node_.doDefault();
     this.exit();
     return true;
-  },
+  }
 
   /**
    * Get the menu node. If it's not defined, search for it.
    * @return {!chrome.automation.AutomationNode}
    */
-  menuNode: function() {
+  menuNode() {
     if (this.menuNode_)
       return this.menuNode_;
 
-    let treeWalker = new AutomationTreeWalker(
+    const treeWalker = new AutomationTreeWalker(
         this.desktop_, constants.Dir.FORWARD,
         SwitchAccessPredicate.contextMenuDiscoveryRestrictions());
-    treeWalker.next();
-    if (treeWalker.node) {
-      this.menuNode_ = treeWalker.node;
+    const node = treeWalker.next().node;
+    if (node) {
+      this.menuNode_ = node;
       return this.menuNode_;
     }
     console.log('Unable to find the context menu.');
     return this.desktop_;
-  },
+  }
 
   /**
    * Clear the focus ring.
    * @private
    */
-  clearFocusRing_: function() {
+  clearFocusRing_() {
     this.updateFocusRing_(true);
-  },
+  }
+
+  /**
+   * @private
+   */
+  init_() {
+    // Listen for messages from the menu.
+    window.addEventListener('message', this.onMessageReceived_.bind(this));
+  }
 
   /**
    * Receive a message from the context menu, and perform the appropriate
    * action.
    * @private
    */
-  onMessageReceived_: function(event) {
+  onMessageReceived_(event) {
     this.exit();
 
     if (event.data === ContextMenuManager.Action.CLICK)
@@ -223,7 +202,7 @@ ContextMenuManager.prototype = {
         event.data === ContextMenuManager.Action.SCROLL_LEFT ||
         event.data === ContextMenuManager.Action.SCROLL_RIGHT)
       this.automationManager_.scroll(event.data);
-  },
+  }
 
   /**
    * Send a message to the context menu to update the focus ring around the
@@ -232,12 +211,34 @@ ContextMenuManager.prototype = {
    * @private
    * @param {boolean=} opt_clear If true, will clear the focus ring.
    */
-  updateFocusRing_: function(opt_clear) {
+  updateFocusRing_(opt_clear) {
     if (!this.node_)
       return;
-    let id = this.node_.htmlAttributes.id;
-    let onOrOff = opt_clear ? 'off' : 'on';
+    const id = this.node_.htmlAttributes.id;
+    const onOrOff = opt_clear ? 'off' : 'on';
     MessageHandler.sendMessage(
         MessageHandler.Destination.PANEL, 'setFocusRing', [id, onOrOff]);
   }
+}
+
+/**
+ * Actions available in the Context Menu.
+ * @enum {string}
+ * @const
+ */
+ContextMenuManager.Action = {
+  CLICK: 'click',
+  OPTIONS: 'options',
+  SCROLL_BACKWARD: 'scroll-backward',
+  SCROLL_DOWN: 'scroll-down',
+  SCROLL_FORWARD: 'scroll-forward',
+  SCROLL_LEFT: 'scroll-left',
+  SCROLL_RIGHT: 'scroll-right',
+  SCROLL_UP: 'scroll-up'
 };
+
+/**
+ * The ID for the div containing the context menu.
+ * @const
+ */
+ContextMenuManager.MenuId = 'switchaccess_contextmenu_actions';

chrome/browser/resources/chromeos/switch_access/keyboard_handler.js

@@ -4,56 +4,35 @@
 
 /**
  * Class to handle keyboard input.
- *
- * @constructor
- * @param {SwitchAccessInterface} switchAccess
  */
-function KeyboardHandler(switchAccess) {
+class KeyboardHandler {
   /**
-   * SwitchAccess reference.
-   *
-   * @private {SwitchAccessInterface}
+   * @param {!SwitchAccessInterface} switchAccess
    */
-  this.switchAccess_ = switchAccess;
+  constructor(switchAccess) {
+    /**
+     * SwitchAccess reference.
+     * @private {!SwitchAccessInterface}
+     */
+    this.switchAccess_ = switchAccess;
 
-  this.init_();
-}
-
-KeyboardHandler.prototype = {
-  /**
-   * Set up key listener.
-   *
-   * @private
-   */
-  init_: function() {
-    this.updateSwitchAccessKeys();
-    document.addEventListener('keyup', this.handleKeyEvent_.bind(this));
-  },
+    this.init_();
+  }
 
   /**
    * Update the keyboard keys captured by Switch Access to those stored in
    * prefs.
    */
-  updateSwitchAccessKeys: function() {
+  updateSwitchAccessKeys() {
     let keyCodes = [];
-    for (let command of this.switchAccess_.getCommands()) {
-      let keyCode = this.keyCodeFor_(command);
+    for (const command of this.switchAccess_.getCommands()) {
+      const keyCode = this.keyCodeFor_(command);
       if ((keyCode >= '0'.charCodeAt(0) && keyCode <= '9'.charCodeAt(0)) ||
           (keyCode >= 'A'.charCodeAt(0) && keyCode <= 'Z'.charCodeAt(0)))
         keyCodes.push(keyCode);
     }
     chrome.accessibilityPrivate.setSwitchAccessKeys(keyCodes);
-  },
-
-  /**
-   * Return the key code that |command| maps to.
-   *
-   * @param {string} command
-   * @return {number}
-   */
-  keyCodeFor_: function(command) {
-    return this.switchAccess_.getNumberPref(command);
-  },
+  }
 
   /**
    * Run the command associated with the passed keyboard event.
@@ -61,14 +40,32 @@ KeyboardHandler.prototype = {
    * @param {!Event} event
    * @private
    */
-  handleKeyEvent_: function(event) {
-    for (let command of this.switchAccess_.getCommands()) {
+  handleKeyEvent_(event) {
+    for (const command of this.switchAccess_.getCommands()) {
       if (this.keyCodeFor_(command) === event.keyCode) {
-        let key = event.key.toUpperCase();
         this.switchAccess_.runCommand(command);
         this.switchAccess_.performedUserAction();
         return;
       }
     }
-  },
-};
+  }
+
+  /**
+   * Set up key listener.
+   * @private
+   */
+  init_() {
+    this.updateSwitchAccessKeys();
+    document.addEventListener('keyup', this.handleKeyEvent_.bind(this));
+  }
+
+  /**
+   * Return the key code that |command| maps to.
+   *
+   * @param {string} command
+   * @return {number}
+   */
+  keyCodeFor_(command) {
+    return this.switchAccess_.getNumberPref(command);
+  }
+}

chrome/browser/resources/chromeos/switch_access/message_handler.js

@@ -3,55 +3,47 @@
 // found in the LICENSE file.
 
 /**
- * Class to handle sending messages between the background page and the
- * context menu.
- *
- * @constructor
+ * Handles sending messages between the background page and the context menu.
  */
-function MessageHandler() {}
+const MessageHandler = {
+  /**
+   * function setActions() takes a list of comma-separated action names,
+   * containing only letters and hyphens.
+   */
+  SET_ACTIONS_REGEX: /setActions[(]((?:[a-zA-Z-]+,)*[a-zA-Z-]+)[)]/,
 
-/**
- * function setActions() takes a list of comma-separated action names,
- * containing only letters and hyphens.
- */
-MessageHandler.SET_ACTIONS_REGEX =
-    /setActions[(]((?:[a-zA-Z-]+,)*[a-zA-Z-]+)[)]/;
-
-/**
- * function setFocusRing() takes one element ID, containing only letters,
- * hyphens, and underscores, and either 'on' or 'off'.
- */
-MessageHandler.SET_FOCUS_RING_REGEX =
-    /setFocusRing[(]([a-zA-Z_-]+),((?:on)|(?:off))[)]/;
+  /**
+   * function setFocusRing() takes one element ID, containing only letters,
+   * hyphens, and underscores, and either 'on' or 'off'.
+   */
+  SET_FOCUS_RING_REGEX: /setFocusRing[(]([a-zA-Z_-]+),((?:on)|(?:off))[)]/,
 
-/**
- * The possible destinations for messages.
- * @enum {string}
- * @const
- */
-MessageHandler.Destination = {
-  BACKGROUND: 'background',
-  PANEL: 'panel.html'
-};
+  /**
+   * The possible destinations for messages.
+   * @enum {string}
+   * @const
+   */
+  Destination: {BACKGROUND: 'background', PANEL: 'panel.html'},
 
-/**
- * Sends a message to the Context Menu panel with the given name and
- * parameters.
- *
- * @param {!MessageHandler.Destination} destination
- * @param {string} messageName
- * @param {Array<string>=} params
- */
-MessageHandler.sendMessage = function(destination, messageName, params) {
-  let message = messageName;
-  if (params)
-    message += '(' + params.join(',') + ')';
+  /**
+   * Sends a message to the Context Menu panel with the given name and
+   * parameters.
+   *
+   * @param {!MessageHandler.Destination} destination
+   * @param {string} messageName
+   * @param {Array<string>=} opt_params
+   */
+  sendMessage: (destination, messageName, opt_params) => {
+    let message = messageName;
+    if (opt_params)
+      message += '(' + opt_params.join(',') + ')';
 
-  let views = chrome.extension.getViews() || [];
-  for (let view of views)
-    if (view && view.location.href.includes(destination)) {
-      view.postMessage(message, window.location.origin);
-      return;
-    }
-  console.log('Couldn\'t find ' << destination);
+    const views = chrome.extension.getViews() || [];
+    for (const view of views)
+      if (view && view.location.href.includes(destination)) {
+        view.postMessage(message, window.location.origin);
+        return;
+      }
+    console.log('Couldn\'t find ', destination);
+  }
 };

chrome/browser/resources/chromeos/switch_access/options.js

@@ -4,43 +4,41 @@
 
 /**
  * Class to manage the options page.
- *
- * @constructor
  */
-function SwitchAccessOptions() {
-  let background = chrome.extension.getBackgroundPage();
+class SwitchAccessOptions {
+  constructor() {
+    const background = chrome.extension.getBackgroundPage();
 
-  /**
-   * SwitchAccess reference.
-   *
-   * @private {SwitchAccessInterface}
-   */
-  this.switchAccess_ = background.switchAccess;
+    /**
+     * SwitchAccess reference.
+     * @private {!SwitchAccessInterface}
+     */
+    this.switchAccess_ = background.switchAccess;
 
-  this.init_();
-  document.addEventListener('change', this.handleInputChange_.bind(this));
-  background.document.addEventListener(
-      'prefsUpdate', this.handlePrefsUpdate_.bind(this));
-}
+    this.init_();
+
+    document.addEventListener('change', this.handleInputChange_.bind(this));
+    background.document.addEventListener(
+        'prefsUpdate', this.handlePrefsUpdate_.bind(this));
+  }
 
-SwitchAccessOptions.prototype = {
   /**
    * Initialize the options page by setting all elements representing a user
    * preference to show the correct value.
    *
    * @private
    */
-  init_: function() {
+  init_() {
     document.getElementById('enableAutoScan').checked =
         this.switchAccess_.getBooleanPref('enableAutoScan');
     document.getElementById('autoScanTime').value =
         this.switchAccess_.getNumberPref('autoScanTime') / 1000;
 
-    for (let command of this.switchAccess_.getCommands()) {
+    for (const command of this.switchAccess_.getCommands()) {
       document.getElementById(command).value =
           String.fromCharCode(this.switchAccess_.getNumberPref(command));
     }
-  },
+  }
 
   /**
    * Handle a change by the user to an element representing a user preference.
@@ -48,16 +46,16 @@ SwitchAccessOptions.prototype = {
    * @param {!Event} event
    * @private
    */
-  handleInputChange_: function(event) {
-    let input = event.target;
+  handleInputChange_(event) {
+    const input = event.target;
     switch (input.id) {
       case 'enableAutoScan':
         this.switchAccess_.setPref(input.id, input.checked);
         break;
       case 'autoScanTime':
-        let oldVal = this.switchAccess_.getNumberPref(input.id);
-        let val = Number(input.value) * 1000;
-        let min = Number(input.min) * 1000;
+        const oldVal = this.switchAccess_.getNumberPref(input.id);
+        const val = Number(input.value) * 1000;
+        const min = Number(input.min) * 1000;
         if (this.isValidScanTimeInput_(val, oldVal, min)) {
           input.value = Number(input.value);
           this.switchAccess_.setPref(input.id, val);
@@ -67,17 +65,17 @@ SwitchAccessOptions.prototype = {
         break;
       default:
         if (this.switchAccess_.getCommands().includes(input.id)) {
-          let keyCode = input.value.toUpperCase().charCodeAt(0);
+          const keyCode = input.value.toUpperCase().charCodeAt(0);
           if (this.isValidKeyCode_(keyCode)) {
             input.value = input.value.toUpperCase();
             this.switchAccess_.setPref(input.id, keyCode);
           } else {
-            let oldKeyCode = this.switchAccess_.getNumberPref(input.id);
+            const oldKeyCode = this.switchAccess_.getNumberPref(input.id);
             input.value = String.fromCharCode(oldKeyCode);
           }
         }
     }
-  },
+  }
 
   /**
    * Return true if |keyCode| is a letter or number, and if it is not already
@@ -86,11 +84,11 @@ SwitchAccessOptions.prototype = {
    * @param {number} keyCode
    * @return {boolean}
    */
-  isValidKeyCode_: function(keyCode) {
+  isValidKeyCode_(keyCode) {
     return ((keyCode >= '0'.charCodeAt(0) && keyCode <= '9'.charCodeAt(0)) ||
             (keyCode >= 'A'.charCodeAt(0) && keyCode <= 'Z'.charCodeAt(0))) &&
         !this.switchAccess_.keyCodeIsUsed(keyCode);
-  },
+  }
 
   /**
    * Return true if the input is a valid autoScanTime input. Otherwise, return
@@ -101,9 +99,9 @@ SwitchAccessOptions.prototype = {
    * @param {number} min
    * @return {boolean}
    */
-  isValidScanTimeInput_: function(value, oldValue, min) {
+  isValidScanTimeInput_(value, oldValue, min) {
     return (value !== oldValue) && (value >= min);
-  },
+  }
 
   /**
    * Handle a change in user preferences.
@@ -111,8 +109,8 @@ SwitchAccessOptions.prototype = {
    * @param {!Event} event
    * @private
    */
-  handlePrefsUpdate_: function(event) {
-    let updatedPrefs = event.detail;
+  handlePrefsUpdate_(event) {
+    const updatedPrefs = event.detail;
     for (let key of Object.keys(updatedPrefs)) {
       switch (key) {
         case 'enableAutoScan':
@@ -128,7 +126,7 @@ SwitchAccessOptions.prototype = {
       }
     }
   }
-};
+}
 
 document.addEventListener('DOMContentLoaded', function() {
   new SwitchAccessOptions();

chrome/browser/resources/chromeos/switch_access/prefs.js

@@ -4,32 +4,61 @@
 
 /**
  * Class to manage user preferences.
- *
- * @constructor
- * @param {SwitchAccessInterface} switchAccess
  */
-function SwitchAccessPrefs(switchAccess) {
+class SwitchAccessPrefs {
   /**
-   * SwitchAccess reference.
-   *
-   * @private {SwitchAccessInterface}
+   * @param {!SwitchAccessInterface} switchAccess
    */
-  this.switchAccess_ = switchAccess;
+  constructor(switchAccess) {
+    /**
+     * SwitchAccess reference.
+     * @private {!SwitchAccessInterface}
+     */
+    this.switchAccess_ = switchAccess;
+
+    /**
+     * User preferences, initially set to the default preference values.
+     * @private
+     */
+    this.prefs_ = Object.assign({}, DEFAULT_PREFS);
+
+    this.init_();
+  }
 
   /**
-   * User preferences, initially set to the default preference values.
+   * Store any changes from chrome.storage.sync to this.prefs_, if this.prefs_
+   * is not already set to that value. If this.prefs_ changes, fire a
+   * prefsUpdate event.
    *
+   * @param {!Object} storageChanges
+   * @param {string} areaName
+   * @private
+   */
+  handleStorageChange_(storageChanges, areaName) {
+    let updatedPrefs = {};
+    for (const key of Object.keys(storageChanges)) {
+      if (this.prefs_[key] !== storageChanges[key].newValue) {
+        this.prefs_[key] = storageChanges[key].newValue;
+        updatedPrefs[key] = storageChanges[key].newValue;
+      }
+    }
+    if (Object.keys(updatedPrefs).length > 0) {
+      let event = new CustomEvent('prefsUpdate', {'detail': updatedPrefs});
+      document.dispatchEvent(event);
+    }
+  }
+
+  /**
    * @private
    */
-  this.prefs_ = Object.assign({}, this.DEFAULT_PREFS);
-  for (let command of this.switchAccess_.getCommands())
-    this.prefs_[command] = this.switchAccess_.getDefaultKeyCodeFor(command);
+  init_() {
+    for (const command of this.switchAccess_.getCommands())
+      this.prefs_[command] = this.switchAccess_.getDefaultKeyCodeFor(command);
 
-  this.loadPrefs_();
-  chrome.storage.onChanged.addListener(this.handleStorageChange_.bind(this));
-}
+    this.loadPrefs_();
+    chrome.storage.onChanged.addListener(this.handleStorageChange_.bind(this));
+  }
 
-SwitchAccessPrefs.prototype = {
   /**
    * Asynchronously load the current preferences from chrome.storage.sync and
    * store them in this.prefs_, if this.prefs_ is not already set to that value.
@@ -37,45 +66,24 @@ SwitchAccessPrefs.prototype = {
    *
    * @private
    */
-  loadPrefs_: function() {
-    let defaultKeys = Object.keys(this.prefs_);
-    chrome.storage.sync.get(defaultKeys, function(loadedPrefs) {
+  loadPrefs_() {
+    const defaultKeys = Object.keys(this.prefs_);
+    chrome.storage.sync.get(defaultKeys, (loadedPrefs) => {
       let updatedPrefs = {};
-      for (let key of Object.keys(loadedPrefs)) {
+
+      for (const key of Object.keys(loadedPrefs)) {
         if (this.prefs_[key] !== loadedPrefs[key]) {
           this.prefs_[key] = loadedPrefs[key];
           updatedPrefs[key] = loadedPrefs[key];
         }
       }
+
       if (Object.keys(updatedPrefs).length > 0) {
-        let event = new CustomEvent('prefsUpdate', {'detail': updatedPrefs});
+        const event = new CustomEvent('prefsUpdate', {'detail': updatedPrefs});
         document.dispatchEvent(event);
       }
-    }.bind(this));
-  },
-
-  /**
-   * Store any changes from chrome.storage.sync to this.prefs_, if this.prefs_
-   * is not already set to that value. If this.prefs_ changes, fire a
-   * prefsUpdate event.
-   *
-   * @param {!Object} storageChanges
-   * @param {string} areaName
-   * @private
-   */
-  handleStorageChange_: function(storageChanges, areaName) {
-    let updatedPrefs = {};
-    for (let key of Object.keys(storageChanges)) {
-      if (this.prefs_[key] !== storageChanges[key].newValue) {
-        this.prefs_[key] = storageChanges[key].newValue;
-        updatedPrefs[key] = storageChanges[key].newValue;
-      }
-    }
-    if (Object.keys(updatedPrefs).length > 0) {
-      let event = new CustomEvent('prefsUpdate', {'detail': updatedPrefs});
-      document.dispatchEvent(event);
-    }
-  },
+    });
+  }
 
   /**
    * Set the value of the preference |key| to |value| in chrome.storage.sync.
@@ -84,11 +92,11 @@ SwitchAccessPrefs.prototype = {
    * @param {string} key
    * @param {boolean|string|number} value
    */
-  setPref: function(key, value) {
+  setPref(key, value) {
     let pref = {};
     pref[key] = value;
     chrome.storage.sync.set(pref);
-  },
+  }
 
   /**
    * Get the value of type 'boolean' of the preference |key|. Will throw a type
@@ -97,13 +105,13 @@ SwitchAccessPrefs.prototype = {
    * @param  {string} key
    * @return {boolean}
    */
-  getBooleanPref: function(key) {
-    let value = this.prefs_[key];
+  getBooleanPref(key) {
+    const value = this.prefs_[key];
     if (typeof value === 'boolean')
       return value;
     else
       throw new TypeError('No value of boolean type for key \'' + key + '\'');
-  },
+  }
 
   /**
    * Get the value of type 'number' of the preference |key|. Will throw a type
@@ -112,13 +120,13 @@ SwitchAccessPrefs.prototype = {
    * @param  {string} key
    * @return {number}
    */
-  getNumberPref: function(key) {
-    let value = this.prefs_[key];
+  getNumberPref(key) {
+    const value = this.prefs_[key];
     if (typeof value === 'number')
       return value;
     else
       throw new TypeError('No value of number type for key \'' + key + '\'');
-  },
+  }
 
   /**
    * Get the value of type 'string' of the preference |key|. Will throw a type
@@ -127,13 +135,13 @@ SwitchAccessPrefs.prototype = {
    * @param  {string} key
    * @return {string}
    */
-  getStringPref: function(key) {
-    let value = this.prefs_[key];
+  getStringPref(key) {
+    const value = this.prefs_[key];
     if (typeof value === 'string')
       return value;
     else
       throw new TypeError('No value of string type for key \'' + key + '\'');
-  },
+  }
 
   /**
    * Returns true if |keyCode| is already used to run a command from the
@@ -142,19 +150,20 @@ SwitchAccessPrefs.prototype = {
    * @param {number} keyCode
    * @return {boolean}
    */
-  keyCodeIsUsed: function(keyCode) {
-    for (let command of this.switchAccess_.getCommands()) {
+  keyCodeIsUsed(keyCode) {
+    for (const command of this.switchAccess_.getCommands()) {
       if (keyCode === this.prefs_[command])
         return true;
     }
     return false;
-  },
+  }
+}
 
-  /**
-   * The default value of all preferences besides command keyboard bindings.
-   * All preferences should be primitives to prevent changes to default values.
-   *
-   * @const
-   */
-  DEFAULT_PREFS: {'enableAutoScan': false, 'autoScanTime': 800}
+/**
+ * The default value of all preferences besides command keyboard bindings.
+ * All preferences should be primitives to prevent changes to default values.
+ */
+const DEFAULT_PREFS = {
+  'enableAutoScan': false,
+  'autoScanTime': 800
 };

chrome/browser/resources/chromeos/switch_access/switch_access.js

@@ -4,59 +4,51 @@
 
 /**
  * Class to manage SwitchAccess and interact with other controllers.
- *
- * @constructor
  * @implements {SwitchAccessInterface}
  */
-function SwitchAccess() {
-  console.log('Switch access is enabled');
-
-  /**
-   * User commands.
-   *
-   * @private {Commands}
-   */
-  this.commands_ = null;
-
-  /**
-   * User preferences.
-   *
-   * @private {SwitchAccessPrefs}
-   */
-  this.switchAccessPrefs_ = null;
-
-  /**
-   * Handles changes to auto-scan.
-   *
-   * @private {AutoScanManager}
-   */
-  this.autoScanManager_ = null;
-
-  /**
-   * Handles keyboard input.
-   *
-   * @private {KeyboardHandler}
-   */
-  this.keyboardHandler_ = null;
-
-  /**
-   * Handles interactions with the accessibility tree, including moving to and
-   * selecting nodes.
-   *
-   * @private {AutomationManager}
-   */
-  this.automationManager_ = null;
-
-  this.init_();
-}
+class SwitchAccess {
+  constructor() {
+    console.log('Switch access is enabled');
+
+    /**
+     * User commands.
+     * @private {Commands}
+     */
+    this.commands_ = null;
+
+    /**
+     * User preferences.
+     * @private {SwitchAccessPrefs}
+     */
+    this.switchAccessPrefs_ = null;
+
+    /**
+     * Handles changes to auto-scan.
+     * @private {AutoScanManager}
+     */
+    this.autoScanManager_ = null;
+
+    /**
+     * Handles keyboard input.
+     * @private {KeyboardHandler}
+     */
+    this.keyboardHandler_ = null;
+
+    /**
+     * Handles interactions with the accessibility tree, including moving to and
+     * selecting nodes.
+     * @private {AutomationManager}
+     */
+    this.automationManager_ = null;
+
+    this.init_();
+  }
 
-SwitchAccess.prototype = {
   /**
    * Set up preferences, controllers, and event listeners.
-   *
    * @private
    */
-  init_: function() {
+  init_() {
     this.commands_ = new Commands(this);
     this.switchAccessPrefs_ = new SwitchAccessPrefs(this);
     this.autoScanManager_ = new AutoScanManager(this);
@@ -68,105 +60,98 @@ SwitchAccess.prototype = {
 
     document.addEventListener(
         'prefsUpdate', this.handlePrefsUpdate_.bind(this));
-  },
+  }
 
   /**
    * Jump to the context menu.
    * @override
    */
-  enterContextMenu: function() {
+  enterContextMenu() {
     if (this.automationManager_)
       this.automationManager_.enterContextMenu();
-  },
+  }
 
   /**
    * Move to the next interesting node.
    * @override
    */
-  moveForward: function() {
+  moveForward() {
     if (this.automationManager_)
       this.automationManager_.moveForward();
-  },
+  }
 
   /**
    * Move to the previous interesting node.
    * @override
    */
-  moveBackward: function() {
+  moveBackward() {
     if (this.automationManager_)
       this.automationManager_.moveBackward();
-  },
+  }
 
   /**
    * Perform the default action on the current node.
-   *
    * @override
    */
-  selectCurrentNode: function() {
+  selectCurrentNode() {
     if (this.automationManager_)
       this.automationManager_.selectCurrentNode();
-  },
+  }
 
   /**
    * Open the options page in a new tab.
-   *
    * @override
    */
-  showOptionsPage: function() {
-    let optionsPage = {url: 'options.html'};
+  showOptionsPage() {
+    const optionsPage = {url: 'options.html'};
     chrome.tabs.create(optionsPage);
-  },
+  }
 
   /**
    * Return a list of the names of all user commands.
-   *
    * @override
    * @return {!Array<string>}
    */
-  getCommands: function() {
+  getCommands() {
     return this.commands_.getCommands();
-  },
+  }
 
   /**
    * Return the default key code for a command.
-   *
    * @override
    * @param {string} command
    * @return {number}
    */
-  getDefaultKeyCodeFor: function(command) {
+  getDefaultKeyCodeFor(command) {
     return this.commands_.getDefaultKeyCodeFor(command);
-  },
+  }
 
   /**
    * Run the function binding for the specified command.
-   *
    * @override
    * @param {string} command
    */
-  runCommand: function(command) {
+  runCommand(command) {
     this.commands_.runCommand(command);
-  },
+  }
 
   /**
    * Perform actions as the result of actions by the user. Currently, restarts
    * auto-scan if it is enabled.
-   *
    * @override
    */
-  performedUserAction: function() {
+  performedUserAction() {
     this.autoScanManager_.restartIfRunning();
-  },
+  }
 
   /**
    * Handle a change in user preferences.
-   *
    * @param {!Event} event
    * @private
    */
-  handlePrefsUpdate_: function(event) {
-    let updatedPrefs = event.detail;
-    for (let key of Object.keys(updatedPrefs)) {
+  handlePrefsUpdate_(event) {
+    const updatedPrefs = event.detail;
+    for (const key of Object.keys(updatedPrefs)) {
       switch (key) {
         case 'enableAutoScan':
           this.autoScanManager_.setEnabled(updatedPrefs[key]);
@@ -179,7 +164,7 @@ SwitchAccess.prototype = {
             this.keyboardHandler_.updateSwitchAccessKeys();
       }
     }
-  },
+  }
 
   /**
    * Set the value of the preference |key| to |value| in chrome.storage.sync.
@@ -189,9 +174,9 @@ SwitchAccess.prototype = {
    * @param {string} key
    * @param {boolean|string|number} value
    */
-  setPref: function(key, value) {
+  setPref(key, value) {
     this.switchAccessPrefs_.setPref(key, value);
-  },
+  }
 
   /**
    * Get the value of type 'boolean' of the preference |key|. Will throw a type
@@ -201,9 +186,9 @@ SwitchAccess.prototype = {
    * @param  {string} key
    * @return {boolean}
    */
-  getBooleanPref: function(key) {
+  getBooleanPref(key) {
     return this.switchAccessPrefs_.getBooleanPref(key);
-  },
+  }
 
   /**
    * Get the value of type 'number' of the preference |key|. Will throw a type
@@ -213,9 +198,9 @@ SwitchAccess.prototype = {
    * @param  {string} key
    * @return {number}
    */
-  getNumberPref: function(key) {
+  getNumberPref(key) {
     return this.switchAccessPrefs_.getNumberPref(key);
-  },
+  }
 
   /**
    * Get the value of type 'string' of the preference |key|. Will throw a type
@@ -225,9 +210,9 @@ SwitchAccess.prototype = {
    * @param  {string} key
    * @return {string}
    */
-  getStringPref: function(key) {
+  getStringPref(key) {
     return this.switchAccessPrefs_.getStringPref(key);
-  },
+  }
 
   /**
    * Returns true if |keyCode| is already used to run a command from the
@@ -237,7 +222,7 @@ SwitchAccess.prototype = {
    * @param {number} keyCode
    * @return {boolean}
    */
-  keyCodeIsUsed: function(keyCode) {
+  keyCodeIsUsed(keyCode) {
     return this.switchAccessPrefs_.keyCodeIsUsed(keyCode);
   }
-};
+}

chrome/browser/resources/chromeos/switch_access/switch_access_interface.js

@@ -4,43 +4,39 @@
 
 /**
  * Interface for controllers to interact with main SwitchAccess class.
- *
  * @interface
  */
-function SwitchAccessInterface() {}
-
-SwitchAccessInterface.prototype = {
+class SwitchAccessInterface {
   /**
    * Jump to the context menu.
    */
-  enterContextMenu: function() {},
+  enterContextMenu() {}
 
   /**
    * Move to the next interesting node.
    */
-  moveForward: function() {},
+  moveForward() {}
 
   /**
    * Move to the previous interesting node.
    */
-  moveBackward: function() {},
+  moveBackward() {}
 
   /**
    * Perform the default action on the current node.
    */
-  selectCurrentNode: function() {},
+  selectCurrentNode() {}
 
   /**
    * Open the options page in a new tab.
    */
-  showOptionsPage: function() {},
+  showOptionsPage() {}
 
   /**
    * Return a list of the names of all user commands.
-   *
    * @return {!Array<string>}
    */
-  getCommands: function() {},
+  getCommands() {}
 
   /**
    * Return the default key code for a command.
@@ -48,20 +44,19 @@ SwitchAccessInterface.prototype = {
    * @param {string} command
    * @return {number}
    */
-  getDefaultKeyCodeFor: function(command) {},
+  getDefaultKeyCodeFor(command) {}
 
   /**
    * Run the function binding for the specified command.
-   *
    * @param {string} command
    */
-  runCommand: function(command) {},
+  runCommand(command) {}
 
   /**
    * Perform actions as the result of actions by the user. Currently, restarts
    * auto-scan if it is enabled.
    */
-  performedUserAction: function() {},
+  performedUserAction() {}
 
   /**
    * Set the value of the preference |key| to |value| in chrome.storage.sync.
@@ -70,7 +65,7 @@ SwitchAccessInterface.prototype = {
    * @param {string} key
    * @param {boolean|string|number} value
    */
-  setPref: function(key, value) {},
+  setPref(key, value) {}
 
   /**
    * Get the value of type 'boolean' of the preference |key|. Will throw a type
@@ -79,7 +74,7 @@ SwitchAccessInterface.prototype = {
    * @param  {string} key
    * @return {boolean}
    */
-  getBooleanPref: function(key) {},
+  getBooleanPref(key) {}
 
   /**
    * Get the value of type 'number' of the preference |key|. Will throw a type
@@ -88,7 +83,7 @@ SwitchAccessInterface.prototype = {
    * @param  {string} key
    * @return {number}
    */
-  getNumberPref: function(key) {},
+  getNumberPref(key) {}
 
   /**
    * Get the value of type 'string' of the preference |key|. Will throw a type
@@ -97,7 +92,7 @@ SwitchAccessInterface.prototype = {
    * @param  {string} key
    * @return {string}
    */
-  getStringPref: function(key) {},
+  getStringPref(key) {}
 
   /**
    * Returns true if |keyCode| is already used to run a command from the
@@ -106,5 +101,5 @@ SwitchAccessInterface.prototype = {
    * @param {number} keyCode
    * @return {boolean}
    */
-  keyCodeIsUsed: function(keyCode) {}
-};
+  keyCodeIsUsed(keyCode) {}
+}

chrome/browser/resources/chromeos/switch_access/test_support.js

@@ -2,22 +2,21 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-function TestSupport() {}
 
-TestSupport.prototype = {
+const TestSupport = {
   /**
    * Connect |parent| and |children| to each other.
    *
    * @param {!Object} parent
    * @param {Array<Object>} children
    */
-  setChildren: function(parent, children) {
+  setChildren: (parent, children) => {
     // Connect parent to its children.
     parent.children = children;
     parent.firstChild = children[0];
     parent.lastChild = children[children.length - 1];
 
-    for (let i = 0; i < children.length; i++) {
+    for (const i = 0; i < children.length; i++) {
       let child = children[i];
 
       // Connect children to their parent.