Interface for requestSources through UserMediaController/Client.

Source/modules/mediastream/MediaStreamTrack.cpp

Index: Source/modules/mediastream/MediaStreamTrack.cpp
diff --git a/Source/modules/mediastream/MediaStreamTrack.cpp b/Source/modules/mediastream/MediaStreamTrack.cpp
index 593d8d6a299aeeb6259af3f40d4276bd6449c115..fd22a6167a735c9fcdb258ab31e7ccb4a73bf760 100644
--- a/Source/modules/mediastream/MediaStreamTrack.cpp
+++ b/Source/modules/mediastream/MediaStreamTrack.cpp
@@ -27,12 +27,14 @@
 #include "modules/mediastream/MediaStreamTrack.h"
 
 #include "bindings/core/v8/ExceptionMessages.h"
+#include "core/dom/Document.h"
 #include "core/dom/ExceptionCode.h"
 #include "core/dom/ExecutionContext.h"
 #include "core/events/Event.h"
 #include "modules/mediastream/MediaStream.h"
 #include "modules/mediastream/MediaStreamTrackSourcesCallback.h"
 #include "modules/mediastream/MediaStreamTrackSourcesRequestImpl.h"
+#include "modules/mediastream/UserMediaController.h"
 #include "platform/mediastream/MediaStreamCenter.h"
 #include "platform/mediastream/MediaStreamComponent.h"
 #include "public/platform/WebSourceInfo.h"
@@ -127,9 +129,14 @@ String MediaStreamTrack::readyState() const
 
 void MediaStreamTrack::getSources(ExecutionContext* context, PassOwnPtrWillBeRawPtr<MediaStreamTrackSourcesCallback> callback, ExceptionState& exceptionState)
 {
+    LocalFrame* frame = toDocument(context)->frame();
+    UserMediaController* userMedia = UserMediaController::from(frame);
+    if (!userMedia) {
+        exceptionState.throwDOMException(NotSupportedError, "No sources controller available; is this a detached window?");

[jochen (gone - plz use gerrit), 2014/09/11 11:35:44]

That's an odd exception. What would a developer do with this? Maybe we should
just return an empty sources list?

[Henrik Grunell, 2014/09/11 11:43:22]

Hmm, I borrowed this from NavigatorMediaStream::webkitGetUserMedia and
NavigatorMediaStream::getMediaDevices. I suppose (hope) it makes sense. :) I
think we should really have a controller. Wdyt?

[jochen (gone - plz use gerrit), 2014/09/11 11:49:21]

ok I guess

[Henrik Grunell, 2014/09/11 11:58:50]

OK. Can you please continue review the CL?

+        return;
+    }
     MediaStreamTrackSourcesRequest* request = MediaStreamTrackSourcesRequestImpl::create(*context, callback);
-    if (!MediaStreamCenter::instance().getMediaStreamTrackSources(request))
-        exceptionState.throwDOMException(NotSupportedError, ExceptionMessages::failedToExecute("getSources", "MediaStreamTrack", "Functionality not implemented yet"));
+    userMedia->requestSources(request);
 }
 
 void MediaStreamTrack::stopTrack(ExceptionState& exceptionState)