Parse meta tag that disables ChromeVox content script and forces compat mode.

chrome/browser/resources/chromeos/chromevox/cvox2/background/background.js

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 /**
  * @fileoverview The entry point for all ChromeVox2 related code for the
  * background page.
  */
 
 goog.provide('Background');
@@ skipping 33 matching lines @@
 
   /**
    * A list of site substring patterns to use with ChromeVox next. Keep these
    * strings relatively specific.
    * @type {!Array<string>}
    * @private
    */
   this.whitelist_ = ['chromevox_next_test'];
 
   /**
+   * A list of site substring patterns to blacklist ChromeVox Classic,
+   * putting ChromeVox into Compat mode.
+   * @type {!Set<string>}
+   * @private
+   */
+  this.classicBlacklist_ = new Set();
+
+  /**
    * Regular expression for blacklisting classic.
    * @type {RegExp}
    * @private
    */
   this.classicBlacklistRegExp_ = Background.globsToRegExp_(
       chrome.runtime.getManifest()['content_scripts'][0]['exclude_globs']);
 
   /**
    * @type {cursors.Range}
    * @private
@@ skipping 159 matching lines @@
           !chrome.commands.onCommand.hasListener(this.onGotCommand))
         chrome.commands.onCommand.addListener(this.onGotCommand);
         chrome.accessibilityPrivate.setKeyboardListener(
             true, cvox.ChromeVox.isStickyPrefOn);
     }
 
     // note that |this.currentRange_| can *change* because the request is
     // async. Save it to ensure we're looking at the currentRange at this moment
     // in time.
     var cur = this.currentRange_;
-    chrome.tabs.query({active: true}, function(tabs) {
+    chrome.tabs.query({active: true,
+                       lastFocusedWindow: true}, function(tabs) {
       if (mode === ChromeVoxMode.CLASSIC) {
         // Generally, we don't want to inject classic content scripts as it is
         // done by the extension system at document load. The exception is when
         // we toggle classic on manually as part of a user command.
         if (opt_injectClassic)
           cvox.ChromeVox.injectChromeVoxIntoTabs(tabs);
       } else {
         // When in compat mode, if the focus is within the desktop tree proper,
         // then do not disable content scripts.
         if (cur && !cur.isWebRange())
           return;
 
-        this.disableClassicChromeVox_();
+        this.disableClassicChromeVox_(tabs);

[David Tseng, 2016/06/16 21:36:33]

If setting force next mode, we do want to disable all running instances of
classic (including those not in a tab).

[dmazzoni, 2016/06/17 22:20:38]

Good catch. Take a look.

       }
     }.bind(this));
 
     // If switching out of a ChromeVox Next mode, make sure we cancel
     // the progress loading sound just in case.
     if ((this.mode_ === ChromeVoxMode.NEXT ||
          this.mode_ === ChromeVoxMode.FORCE_NEXT) &&
         this.mode_ != mode) {
       cvox.ChromeVox.earcons.cancelEarcon(cvox.Earcon.PAGE_START_LOADING);
     }
@@ skipping 738 matching lines @@
         !this.isBlacklistedForClassic_(url) &&
         !this.isWhitelistedForNext_(url);
   },
 
   /**
    * @param {string} url
    * @return {boolean}
    * @private
    */
   isBlacklistedForClassic_: function(url) {
-    return this.classicBlacklistRegExp_.test(url);
+    if (this.classicBlacklistRegExp_.test(url))
+      return true;
+    url = url.substring(0, url.indexOf('#')) || url;
+    return this.classicBlacklist_.has(url);
   },
 
   /**
    * @param {string} url
    * @return {boolean} Whether the given |url| is whitelisted.
    * @private
    */
   isWhitelistedForNext_: function(url) {
     return this.whitelist_.some(function(item) {
       return url.indexOf(item) != -1;
     });
   },
 
   /**
    * Disables classic ChromeVox in current web content.
+   * @param {Array<Tab>} tabs The tabs where ChromeVox scripts should
+   *     be disabled.
    */
-  disableClassicChromeVox_: function() {
-    cvox.ExtensionBridge.send({
+  disableClassicChromeVox_: function(tabs) {
+    for (var i = 0, tab; tab = tabs[i]; i++) {
+      chrome.tabs.sendMessage(tab.id, {
         message: 'SYSTEM_COMMAND',
         command: 'killChromeVox'
-    });
+      });
+    }
   },
 
   /**
    * @param {!Spannable} text
    * @param {number} position
    * @private
    */
   brailleRoutingCommand_: function(text, position) {
     var actionNodeSpan = null;
     var selectionSpan = null;
@@ skipping 31 matching lines @@
 
     switch (target) {
       case 'next':
         if (action == 'getIsClassicEnabled') {
           var url = msg['url'];
           var isClassicEnabled = this.shouldEnableClassicForUrl_(url);
           port.postMessage({
             target: 'next',
             isClassicEnabled: isClassicEnabled
           });
+        } else if (action == 'enableCompatForUrl') {
+          var url = msg['url'];
+          this.classicBlacklist_.add(url);
+          if (this.currentRange_ && this.currentRange_.start.node)
+            this.refreshMode(this.currentRange_.start.node);
         } else if (action == 'onCommand') {
           this.onGotCommand(msg['command']);
         } else if (action == 'flushNextUtterance') {
           Output.flushNextSpeechUtterance();
         }
         break;
     }
   },
 
   /**
@@ skipping 106 matching lines @@
     return glob.replace(/[.+^$(){}|[\]\\]/g, '\\$&')
         .replace(/\*/g, '.*')
         .replace(/\?/g, '.');
   }).join('|') + ')$');
 };
 
 /** @type {Background} */
 global.backgroundObj = new Background();
 
 });  // goog.scope