MediaRecorder: make MediaRecorderHandler a MediaStreamObserver

content/public/renderer/media_stream_api.h

Index: content/public/renderer/media_stream_api.h
diff --git a/content/public/renderer/media_stream_api.h b/content/public/renderer/media_stream_api.h
index dfb2aaf6ea1161d61c513b8634dedc460f98df54..3d268d3a8972b3ee7d3438a16da02455d7dc88be 100644
--- a/content/public/renderer/media_stream_api.h
+++ b/content/public/renderer/media_stream_api.h
@@ -49,6 +49,9 @@ CONTENT_EXPORT bool AddAudioTrackToMediaStream(
     bool is_readonly,
     blink::WebMediaStream* web_stream);
 
+CONTENT_EXPORT void AddMediaStreamTowebMediaStream(
+    blink::WebMediaStream* web_stream);

[perkj_chrome, 2016/01/07 09:18:00]

?

[mcasas, 2016/01/08 00:14:12]

Following the previous explanation, WebTestDelegate is
implemented in 
content/shell/renderer/layout_tests/blink_test_runner.h,
that can only depend on content/public. And I don't
think MediaStream class should be there, instead the
pattern followed is to use media_stream_api.{cc,h} to
"implement" the calls from the WebTestDelegate in a
correct fashion (e.g.
BlinkTestRunner::AddMediaStreamVideoSourceAndTrack() 
etc).

So WebTestDelegate --> BlinkTestRunner --...
-->content/public/renderer/media_stream_api --...
--> content/renderer/media/ real stuff.

But fret not, since this CL will need the approval of
e.g. jochen@ and those points will be reviewed in 
more depth.

+
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_RENDERER_MEDIA_STREAM_API_H_