Protect all uses of JSON.parse against exceptions.

remoting/webapp/client_plugin_async.js

 // Copyright (c) 2012 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
  * Class that wraps low-level details of interacting with the client plugin.
  *
  * This abstracts a <embed> element and controls the plugin which does
  * the actual remoting work. It also handles differences between
@@ skipping 69 matching lines @@
  * compatibility with older API versions.
  *
  * @const
  * @private
  */
 remoting.ClientPluginAsync.prototype.API_MIN_VERSION_ = 5;
 
 /**
  * @param {string} message_str Message from the plugin.
  */
-remoting.ClientPluginAsync.prototype.handleMessage_ = function(message_str) {
+remoting.ClientPluginAsync.prototype.handleMessage_ = function(messageStr) {
   var message = /** @type {{method:string, data:Object.<string,string>}} */
-      JSON.parse(message_str);
+      jsonParseSafe(messageStr);
 
-  if (!('method' in message) || !('data' in message)) {
+  if (!message || !('method' in message) || !('data' in message)) {
     console.error('Received invalid message from the plugin: ' + message_str);
     return;
   }
 
   if (message.method == 'hello') {
     // Reset the size in case we had to enlarge it to support click-to-play.
     this.plugin.width = 0;
     this.plugin.height = 0;
     if (typeof message.data['apiVersion'] != 'number' ||
         typeof message.data['apiMinVersion'] != 'number') {
@@ skipping 272 matching lines @@
     this.plugin.width = width;
     this.plugin.height = height;
     // Center the plugin just underneath the "Connnecting..." dialog.
     var parentNode = this.plugin.parentNode;
     var dialog = document.getElementById('client-dialog');
     var dialogRect = dialog.getBoundingClientRect();
     parentNode.style.top = (dialogRect.bottom + 16) + 'px';
     parentNode.style.left = (window.innerWidth - width) / 2 + 'px';
   }
 };