Allow MediaSession in iframes to be routed

content/browser/media/session/media_session_service_impl.h

Index: content/browser/media/session/media_session_service_impl.h
diff --git a/content/browser/media/session/media_session_service_impl.h b/content/browser/media/session/media_session_service_impl.h
index 37629c37f38cac272a35ea274b9f40d352977b0e..0211522f49151f356ac5e75b026e6ffdc812fffa 100644
--- a/content/browser/media/session/media_session_service_impl.h
+++ b/content/browser/media/session/media_session_service_impl.h
@@ -12,10 +12,12 @@
 
 namespace content {
 
-class MediaSessionImpl;
 class RenderFrameHost;
+class MediaSessionImpl;
 
-// There is one MediaSessionService per frame.
+// There is one MediaSessionService per frame. The class is owned by
+// RenderFrameHost and should register/unregister itself to/from
+// MediaSessionImpl when RenderFrameHost is created/destroyed.
 class MediaSessionServiceImpl : public blink::mojom::MediaSessionService {
  public:
   ~MediaSessionServiceImpl() override;
@@ -23,6 +25,12 @@ class MediaSessionServiceImpl : public blink::mojom::MediaSessionService {
   static void Create(RenderFrameHost* render_frame_host,
                      blink::mojom::MediaSessionServiceRequest request);
   const blink::mojom::MediaSessionClientPtr& GetClient() { return client_; }
+  RenderFrameHost* GetRenderFrameHost() { return render_frame_host_; }
+
+  const base::Optional<MediaMetadata>& metadata() const { return metadata_; }
+  const std::set<blink::mojom::MediaSessionAction>& actions() const {
+    return actions_;
+  }
 
  private:
   explicit MediaSessionServiceImpl(RenderFrameHost* render_frame_host);
@@ -30,14 +38,11 @@ class MediaSessionServiceImpl : public blink::mojom::MediaSessionService {
   // blink::mojom::MediaSessionService implementation.
   void SetClient(blink::mojom::MediaSessionClientPtr client) override;
 
-  void SetMetadata(
-      const base::Optional<content::MediaMetadata>& metadata) override;
+  void SetMetadata(const base::Optional<MediaMetadata>& metadata) override;
 
   void EnableAction(blink::mojom::MediaSessionAction action) override;
   void DisableAction(blink::mojom::MediaSessionAction action) override;
 
-  // Returns the content::MediaSession this service is associated with. Only
-  // returns non-null when this service is in the top-level frame.
   MediaSessionImpl* GetMediaSession();
 
   void Bind(blink::mojom::MediaSessionServiceRequest request);
@@ -48,6 +53,8 @@ class MediaSessionServiceImpl : public blink::mojom::MediaSessionService {
   // The binding is removed when binding_ is cleared or goes out of scope.
   std::unique_ptr<mojo::Binding<blink::mojom::MediaSessionService>> binding_;
   blink::mojom::MediaSessionClientPtr client_;
+  base::Optional<MediaMetadata> metadata_;
+  std::set<blink::mojom::MediaSessionAction> actions_;
 
   DISALLOW_COPY_AND_ASSIGN(MediaSessionServiceImpl);
 };