Implement MediaSession (metadata) per frame [NOT READY, HAS DEPENDENCY]

third_party/WebKit/Source/modules/mediasession/MediaSession.cpp

Index: third_party/WebKit/Source/modules/mediasession/MediaSession.cpp
diff --git a/third_party/WebKit/Source/modules/mediasession/MediaSession.cpp b/third_party/WebKit/Source/modules/mediasession/MediaSession.cpp
index 5f47c82ef3f575561dc51bb84d86787eb00be185..7e89c1f367c6b97ac2a61e4ebcfc25e085ef937d 100644
--- a/third_party/WebKit/Source/modules/mediasession/MediaSession.cpp
+++ b/third_party/WebKit/Source/modules/mediasession/MediaSession.cpp
@@ -28,6 +28,11 @@ MediaSession* MediaSession::create(ExecutionContext* context, ExceptionState& ex
 {
     Document* document = toDocument(context);
     LocalFrame* frame = document->frame();
+    return create(frame, exceptionState);
+}
+
+MediaSession* MediaSession::create(LocalFrame* frame, ExceptionState& exceptionState)
+{
     FrameLoaderClient* client = frame->loader().client();
     std::unique_ptr<WebMediaSession> webMediaSession = client->createWebMediaSession();
     if (!webMediaSession) {
@@ -43,6 +48,7 @@ ScriptPromise MediaSession::activate(ScriptState* scriptState)
     ScriptPromise promise = resolver->promise();
 
     m_webMediaSession->activate(new CallbackPromiseAdapter<void, MediaSessionError>(resolver));
+
     return promise;
 }
 
@@ -58,6 +64,7 @@ ScriptPromise MediaSession::deactivate(ScriptState* scriptState)
 void MediaSession::setMetadata(MediaMetadata* metadata)
 {
     m_metadata = metadata;
+
     if (metadata) {
         WebMediaMetadata webMetadata = (WebMediaMetadata) *metadata;
         m_webMediaSession->setMetadata(&webMetadata);