Fix ChromeVox's detection of whether the current document has focus.

chrome/browser/resources/chromeos/chromevox/host/chrome/braille.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 Bridge that sends Braille messages from content scripts or
  * other pages to the main background page.
  *
  */
 
@@ skipping 31 matching lines @@
    * @private
    */
   this.nextLocalId_ = 1;
   cvox.ExtensionBridge.addMessageListener(goog.bind(function(msg, port) {
     // Since ChromeVox gets injected into multiple iframes on a page, check to
     // ensure that this is the "active" iframe via its focused state.
     // Furthermore, if the active element is itself an iframe, the focus is
     // within the iframe even though the containing document also has focus.
     // Don't process the event if this document isn't focused or focus lies in
     // a descendant.
-    if (!document.hasFocus() || document.activeElement.tagName == 'IFRAME') {
+    if (!cvox.ChromeVox.documentHasFocus()) {
       return;
     }
     if (msg['message'] == 'BRAILLE' && msg['args']) {
       var content = null;
       if (msg['contentId'] == this.lastContentId_) {
         content = this.lastContent_;
       }
       this.commandListener_(msg['args'], content);
     }
   }, this));
@@ skipping 42 matching lines @@
   if (command) {
     command({event: brailleEvt, content: content});
   } else {
     console.error('Unknown braille command: ' + JSON.stringify(brailleEvt));
   }
 };
 
 
 /** Export platform constructor. */
 cvox.HostFactory.brailleConstructor = cvox.ChromeBraille;