Extend components/test_runner's generated WebMediaStream to have a ChromeMock VideoTrack and Source

components/test_runner/mock_web_media_stream_center.cc

Index: components/test_runner/mock_web_media_stream_center.cc
diff --git a/components/test_runner/mock_web_media_stream_center.cc b/components/test_runner/mock_web_media_stream_center.cc
index 3c9206195f19eff75f14ad85d68c10d2f0ad9993..b39674e2bffaebe96d37d58c0b482da254579ce5 100644
--- a/components/test_runner/mock_web_media_stream_center.cc
+++ b/components/test_runner/mock_web_media_stream_center.cc
@@ -36,7 +36,8 @@ class NewTrackTask : public WebMethodTask<MockWebMediaStreamCenter> {
     source.initialize("MagicVideoDevice#1",
                       blink::WebMediaStreamSource::TypeVideo,
                       "Magic video track",
-                      false /* remote */, true /* readonly */);
+                      false /* remote */,
+                      true /* readonly */);
     track.initialize(source);
     stream_.addTrack(track);
   }
@@ -62,7 +63,7 @@ class MockWebAudioDestinationConsumer
 }  // namespace
 
 MockWebMediaStreamCenter::MockWebMediaStreamCenter(
-    blink::WebMediaStreamCenterClient* client,
+    blink::WebMediaStreamCenterClient* /* client */,
     TestInterfaces* interfaces)
     : interfaces_(interfaces) {
 }
@@ -96,13 +97,15 @@ void MockWebMediaStreamCenter::didStopLocalMediaStream(
     const blink::WebMediaStream& stream) {
   blink::WebVector<blink::WebMediaStreamTrack> tracks;
   stream.audioTracks(tracks);
-  for (size_t i = 0; i < tracks.size(); ++i)
-    tracks[i].source().setReadyState(
+  for (const auto& track : tracks) {
+    track.source().setReadyState(
         blink::WebMediaStreamSource::ReadyStateEnded);
+  }
   stream.videoTracks(tracks);
-  for (size_t i = 0; i < tracks.size(); ++i)
-    tracks[i].source().setReadyState(
+  for (const auto& track : tracks) {
+    track.source().setReadyState(
         blink::WebMediaStreamSource::ReadyStateEnded);
+  }
 }
 
 bool MockWebMediaStreamCenter::didStopMediaStreamTrack(
@@ -115,8 +118,8 @@ void MockWebMediaStreamCenter::didCreateMediaStream(
     blink::WebMediaStream& stream) {
   blink::WebVector<blink::WebMediaStreamTrack> audio_tracks;
   stream.audioTracks(audio_tracks);
-  for (size_t i = 0; i < audio_tracks.size(); ++i) {
-    blink::WebMediaStreamSource source = audio_tracks[i].source();
+  for (const auto& audio_track : audio_tracks) {
+    blink::WebMediaStreamSource source = audio_track.source();
     if (source.requiresAudioConsumer()) {
       MockWebAudioDestinationConsumer* consumer =
           new MockWebAudioDestinationConsumer();
@@ -131,7 +134,7 @@ void MockWebMediaStreamCenter::didCreateMediaStream(
 blink::WebAudioSourceProvider*
 MockWebMediaStreamCenter::createWebAudioSourceFromMediaStreamTrack(
     const blink::WebMediaStreamTrack& track) {
-  return NULL;
+  return nullptr;
 }
 
 }  // namespace test_runner