[MediaRouter] Update MR-2-Extension's PostMessage to return boolean.

chrome/browser/media/router/mock_media_router.h

 // 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.
 
 #ifndef CHROME_BROWSER_MEDIA_ROUTER_MOCK_MEDIA_ROUTER_H_
 #define CHROME_BROWSER_MEDIA_ROUTER_MOCK_MEDIA_ROUTER_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 10 matching lines @@
 class MockMediaRouter : public MediaRouter {
  public:
   MockMediaRouter();
   virtual ~MockMediaRouter();
 
   MOCK_METHOD3(CreateRoute,
                void(const MediaSource::Id& source,
                     const MediaSink::Id& sink_id,
                     const MediaRouteResponseCallback& callback));
   MOCK_METHOD1(CloseRoute, void(const MediaRoute::Id& route_id));
-  MOCK_METHOD2(PostMessage,
+  MOCK_METHOD3(SendMessage,
                void(const MediaRoute::Id& route_id,
-                    const std::string& message));
+                    const std::string& message,
+                    const SendMessageCallback& callback));
   MOCK_METHOD1(ClearIssue, void(const Issue::Id& issue_id));
   MOCK_METHOD1(AddIssuesObserver, void(IssuesObserver* observer));
   MOCK_METHOD1(RemoveIssuesObserver, void(IssuesObserver* observer));
 
   MOCK_METHOD1(RegisterMediaSinksObserver, void(MediaSinksObserver* observer));
   MOCK_METHOD1(UnregisterMediaSinksObserver,
                void(MediaSinksObserver* observer));
   MOCK_METHOD1(RegisterMediaRoutesObserver,
                void(MediaRoutesObserver* observer));
   MOCK_METHOD1(UnregisterMediaRoutesObserver,
                void(MediaRoutesObserver* observer));
 };
 
 }  // namespace media_router
 
 #endif  // CHROME_BROWSER_MEDIA_ROUTER_MOCK_MEDIA_ROUTER_H_