Added mute logic to VideoTrackRenderers.

talk/app/webrtc/peerconnectionfactory_unittest.cc

Index: talk/app/webrtc/peerconnectionfactory_unittest.cc
diff --git a/talk/app/webrtc/peerconnectionfactory_unittest.cc b/talk/app/webrtc/peerconnectionfactory_unittest.cc
index 9fb013b54f8e944d8d5216fd6d24a955f140697d..1fdf2ebf149ccb686e08e564c1517f6aa1d5724a 100644
--- a/talk/app/webrtc/peerconnectionfactory_unittest.cc
+++ b/talk/app/webrtc/peerconnectionfactory_unittest.cc
@@ -360,13 +360,15 @@ TEST_F(PeerConnectionFactoryTest, LocalRendering) {
   EXPECT_EQ(0, local_renderer.num_rendered_frames());
   EXPECT_TRUE(capturer->CaptureFrame());
   EXPECT_EQ(1, local_renderer.num_rendered_frames());
+  EXPECT_FALSE(local_renderer.black_frame());
 
   track->set_enabled(false);
   EXPECT_TRUE(capturer->CaptureFrame());
-  EXPECT_EQ(1, local_renderer.num_rendered_frames());
+  EXPECT_EQ(2, local_renderer.num_rendered_frames());
+  EXPECT_TRUE(local_renderer.black_frame());
 
   track->set_enabled(true);
   EXPECT_TRUE(capturer->CaptureFrame());
-  EXPECT_EQ(2, local_renderer.num_rendered_frames());
+  EXPECT_EQ(3, local_renderer.num_rendered_frames());
+  EXPECT_FALSE(local_renderer.black_frame());
 }
-