Add cricket::VideoFrame::frame_id() and set it to RTP timestamp.

webrtc/media/base/videobroadcaster_unittest.cc

Index: webrtc/media/base/videobroadcaster_unittest.cc
diff --git a/webrtc/media/base/videobroadcaster_unittest.cc b/webrtc/media/base/videobroadcaster_unittest.cc
index d2948bb4372546eb8bbe6fd199fdffd25f0b0bfe..58efbf3545628b5f5d43f9ed853baa130d0594cf 100644
--- a/webrtc/media/base/videobroadcaster_unittest.cc
+++ b/webrtc/media/base/videobroadcaster_unittest.cc
@@ -139,8 +139,8 @@ TEST(VideoBroadcasterTest, SinkWantsBlackFrames) {
   // Makes it not all black.
   buffer->InitializeData();
 
-  cricket::WebRtcVideoFrame frame1(
-      buffer, webrtc::kVideoRotation_0, 10 /* timestamp_us */);
+  cricket::WebRtcVideoFrame frame1(buffer, webrtc::kVideoRotation_0,
+                                   10 /* timestamp_us */, 0 /* frame_id */);
   broadcaster.OnFrame(frame1);
   EXPECT_TRUE(sink1.black_frame());
   EXPECT_EQ(10000, sink1.timestamp());
@@ -153,8 +153,8 @@ TEST(VideoBroadcasterTest, SinkWantsBlackFrames) {
   wants2.black_frames = true;
   broadcaster.AddOrUpdateSink(&sink2, wants2);
 
-  cricket::WebRtcVideoFrame frame2(
-      buffer, webrtc::kVideoRotation_0, 30 /* timestamp_us */);
+  cricket::WebRtcVideoFrame frame2(buffer, webrtc::kVideoRotation_0,
+                                   30 /* timestamp_us */, 0 /* frame_id */);
   broadcaster.OnFrame(frame2);
   EXPECT_FALSE(sink1.black_frame());
   EXPECT_EQ(30000, sink1.timestamp());