MediaRecorder: make MediaRecorderHandler a MediaStreamObserver

content/shell/renderer/layout_test/blink_test_runner.cc

Index: content/shell/renderer/layout_test/blink_test_runner.cc
diff --git a/content/shell/renderer/layout_test/blink_test_runner.cc b/content/shell/renderer/layout_test/blink_test_runner.cc
index e8f6f10aa9332f4c566c3ced6a43def543ae44c0..b7b4bcc706000a49a575ddbc4f51e8991e4f3724 100644
--- a/content/shell/renderer/layout_test/blink_test_runner.cc
+++ b/content/shell/renderer/layout_test/blink_test_runner.cc
@@ -53,6 +53,7 @@
 #include "skia/ext/platform_canvas.h"
 #include "third_party/WebKit/public/platform/Platform.h"
 #include "third_party/WebKit/public/platform/WebCString.h"
+#include "third_party/WebKit/public/platform/WebMediaStream.h"
 #include "third_party/WebKit/public/platform/WebPoint.h"
 #include "third_party/WebKit/public/platform/WebRect.h"
 #include "third_party/WebKit/public/platform/WebSize.h"
@@ -789,6 +790,13 @@ bool BlinkTestRunner::AddMediaStreamAudioSourceAndTrack(
 #endif
 }
 
+void BlinkTestRunner::AddMediaStream(blink::WebMediaStream* stream) {
+  DCHECK(stream);
+#if defined(ENABLE_WEBRTC)
+  AddMediaStreamTowebMediaStream(stream);

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

So just to confirm, at this point I cannot just do
stream->setExtraData(new content::MediaStream());
because here I can only depend on content/public
and MediaStream is in content/renderer/media.

Actually it would be possible to move media_stream.{cc,h} 
to content/public/renderer, but I don't think is worth
for testing infrastructure, and would increase the
public API surface of content...

+#endif
+}
+
 // RenderViewObserver  --------------------------------------------------------
 
 void BlinkTestRunner::DidClearWindowObject(WebLocalFrame* frame) {