Make MediaSession available on Desktop

content/browser/media/media_web_contents_observer.h

 // 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.
 
 #ifndef CONTENT_BROWSER_MEDIA_MEDIA_WEB_CONTENTS_OBSERVER_H_
 #define CONTENT_BROWSER_MEDIA_MEDIA_WEB_CONTENTS_OBSERVER_H_
 
 #include <stdint.h>
 
 #include <map>
 #include <memory>
 #include <set>
 
+#include "base/containers/scoped_ptr_hash_map.h"
 #include "base/macros.h"
 #include "content/browser/media/session/media_session_controllers_manager.h"
 #include "content/common/content_export.h"
 #include "content/public/browser/web_contents_observer.h"
 
 #if defined(OS_ANDROID)
 #include "ui/android/view_android.h"
 #endif  // OS_ANDROID
 
 namespace device {
 class PowerSaveBlocker;
 }  // namespace device
 
 namespace media {
 enum class MediaContentType;
 }  // namespace media
 
 namespace content {
 
+class BrowserMediaSessionManager;
+
 // This class manages all RenderFrame based media related managers at the
 // browser side. It receives IPC messages from media RenderFrameObservers and
 // forwards them to the corresponding managers. The managers are responsible
 // for sending IPCs back to the RenderFrameObservers at the render side.
 class CONTENT_EXPORT MediaWebContentsObserver : public WebContentsObserver {
  public:
   explicit MediaWebContentsObserver(WebContents* web_contents);
   ~MediaWebContentsObserver() override;
 
+  // Gets the BrowserMediaSessionManager associated with the given
+  // |render_frame_host|.  Creates a new one if it doesn't exist. The caller
+  // doesn't own the returned pointer.
+  BrowserMediaSessionManager* GetMediaSessionManager(
+      RenderFrameHost* render_frame_host);
+
+  // Sets or overrides the BrowserMediaSessionManager for the given
+  // |render_frame_host|.
+  void SetMediaSessionManagerForTest(
+      RenderFrameHost* render_frame_host,
+      std::unique_ptr<BrowserMediaSessionManager> manager);
+
   // Called by WebContentsImpl when the audible state may have changed.
   void MaybeUpdateAudibleState();
 
   // WebContentsObserver implementation.
   void WebContentsDestroyed() override;
   void RenderFrameDeleted(RenderFrameHost* render_frame_host) override;
   bool OnMessageReceived(const IPC::Message& message,
                          RenderFrameHost* render_frame_host) override;
   void WasShown() override;
   void WasHidden() override;
@@ skipping 50 matching lines @@
                                    std::set<MediaPlayerId>* removed_players);
 
   // Tracking variables and associated power save blockers for media playback.
   ActiveMediaPlayerMap active_audio_players_;
   ActiveMediaPlayerMap active_video_players_;
   std::unique_ptr<device::PowerSaveBlocker> audio_power_save_blocker_;
   std::unique_ptr<device::PowerSaveBlocker> video_power_save_blocker_;
 
   MediaSessionControllersManager session_controllers_manager_;
 
+  // Map from RenderFrameHost* to BrowserMediaSessionManager.
+  using MediaSessionManagerMap =
+      base::ScopedPtrHashMap<RenderFrameHost*,
+                             std::unique_ptr<BrowserMediaSessionManager>>;
+  MediaSessionManagerMap media_session_managers_;
+
   DISALLOW_COPY_AND_ASSIGN(MediaWebContentsObserver);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_MEDIA_MEDIA_WEB_CONTENTS_OBSERVER_H_