Pass media session id over IPC

content/renderer/media/android/renderer_media_session_manager.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 "content/renderer/media/android/renderer_media_session_manager.h"
 
 #include "base/logging.h"
 #include "content/common/media/media_session_messages_android.h"
 #include "content/public/common/media_metadata.h"
 #include "content/public/renderer/render_thread.h"
 #include "content/renderer/media/android/webmediasession_android.h"
 
 namespace content {
 
-static const int kDefaultMediaSessionID = 0;
-
 RendererMediaSessionManager::RendererMediaSessionManager(
     RenderFrame* render_frame)
     : RenderFrameObserver(render_frame),
-      next_session_id_(kDefaultMediaSessionID + 1) {}
+      next_session_id_(blink::WebMediaSession::DefaultID + 1) {}
 
 RendererMediaSessionManager::~RendererMediaSessionManager() {
   DCHECK(sessions_.empty())
       << "RendererMediaSessionManager is owned by RenderFrameImpl and is "
          "destroyed only after all media sessions are destroyed.";
 }
 
 bool RendererMediaSessionManager::OnMessageReceived(const IPC::Message& msg) {
   bool handled = true;
   IPC_BEGIN_MESSAGE_MAP(RendererMediaSessionManager, msg)
@@ skipping 59 matching lines @@
   pending_activation_requests_.Remove(request_id);
 }
 
 void RendererMediaSessionManager::OnDidDeactivate(int request_id) {
   DCHECK(pending_deactivation_requests_.Lookup(request_id)) << request_id;
   pending_deactivation_requests_.Lookup(request_id)->onSuccess();
   pending_deactivation_requests_.Remove(request_id);
 }
 
 }  // namespace content