VideoTrackAdapter: Add passing frames monitor, notify MSVCS -> MSVTrack(s)

content/renderer/media/media_stream_video_source_unittest.cc

Index: content/renderer/media/media_stream_video_source_unittest.cc
diff --git a/content/renderer/media/media_stream_video_source_unittest.cc b/content/renderer/media/media_stream_video_source_unittest.cc
index 71ee6fca7ecd6eb1cdea122d6a5dd8ce3528db4e..eba1af1db9c49909c2e0b4641f22515094eaa0bb 100644
--- a/content/renderer/media/media_stream_video_source_unittest.cc
+++ b/content/renderer/media/media_stream_video_source_unittest.cc
@@ -19,6 +19,10 @@
 #include "media/base/video_frame.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
+using ::testing::_;
+using ::testing::DoAll;
+using ::testing::SaveArg;
+
 namespace content {
 
 ACTION_P(RunClosure, closure) {
@@ -720,4 +724,27 @@ TEST_F(MediaStreamVideoSourceTest, Use0FpsSupportedFormat) {
   MediaStreamVideoSink::RemoveFromVideoTrack(&sink, track);
 }
 
+// Test that a source producing no frames calls back the MSVCS to tell so.
+TEST_F(MediaStreamVideoSourceTest, MutedSource) {
+  MockMediaConstraintFactory factory;
+  blink::WebMediaStreamTrack track =
+      CreateTrackAndStartSource(factory.CreateWebMediaConstraints(),
+                                640, 480, 30);
+
+  MockMediaStreamVideoSink sink;
+  MediaStreamVideoSink::AddToVideoTrack(&sink, sink.GetDeliverFrameCB(), track);
+
+  base::RunLoop run_loop;
+  base::Closure quit_closure = run_loop.QuitClosure();
+  bool muted_state = false;
+  EXPECT_CALL(*mock_source(), SetMutedState(_))
+      .WillOnce(DoAll(SaveArg<0>(&muted_state), RunClosure(quit_closure)));
+  run_loop.Run();
+  // TODO(mcasas): When added, check |track|'s (WebMediaStreamTrack) Muted
+  // attribute, should be false.
+  EXPECT_EQ(muted_state, true);
+
+  MediaStreamVideoSink::RemoveFromVideoTrack(&sink, track);
+}
+
 }  // namespace content