Allow the cast tray to function as expected when the installed extension is missing API methods.

chrome/browser/ui/ash/cast_config_delegate_chromeos.cc

 // Copyright 2015 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.
 
 #include "chrome/browser/ui/ash/cast_config_delegate_chromeos.h"
 
 #include <string>
 
 #include "base/memory/scoped_ptr.h"
 #include "base/strings/utf_string_conversions.h"
@@ skipping 120 matching lines @@
       "backgroundSetup.getMirrorCapableReceiversAndActivities();",
       base::Bind(&GetReceiversAndActivitiesCallback, callback));
 }
 
 void CastConfigDelegateChromeos::CastToReceiver(
     const std::string& receiver_id) {
   ExecuteJavaScript("backgroundSetup.launchDesktopMirroring('" + receiver_id +
                     "');");
 }
 
-void CastConfigDelegateChromeos::StopCasting(const std::string& activity_id) {
+void CastConfigDelegateChromeos::StopCasting() {
   ExecuteJavaScript("backgroundSetup.stopCastMirroring('user-stop');");
+
+  // TODO(jdufault): Remove this after stopCastMirroring is properly exported.
+  // The current beta/release versions of the cast extension do not export
+  // stopCastMirroring, so we will also try to call the minified version.
+  // See crbug.com/489929.
+  ExecuteJavaScript("backgroundSetup.Qu('user-stop');");
 }
 
 void CastConfigDelegateChromeos::LaunchCastOptions() {
   chrome::NavigateParams params(
       ProfileManager::GetActiveUserProfile(),
       FindCastExtension()->GetResourceURL("options.html"),
       ui::PAGE_TRANSITION_LINK);
   params.disposition = NEW_FOREGROUND_TAB;
   params.window_action = chrome::NavigateParams::SHOW_WINDOW;
   chrome::Navigate(&params);
 }
 
 }  // namespace chromeos