Cast: Add JS API to get raw events logs from cast extension.

media/cast/test/sender.cc

Index: media/cast/test/sender.cc
diff --git a/media/cast/test/sender.cc b/media/cast/test/sender.cc
index 4f94a44c26ca3dc6152f13cc8861e6d0c984ea71..ddb23c73db784870f9117e1d78042f1da802a7dc 100644
--- a/media/cast/test/sender.cc
+++ b/media/cast/test/sender.cc
@@ -348,8 +348,7 @@ void WriteLogsToFileAndStopSubscribing(
   VLOG(0) << "Video frame map size: " << frame_events.size();
   VLOG(0) << "Video packet map size: " << packet_events.size();
 
-  // "Assign" stream id 0 for the video events.
-  if (!serializer.SerializeEventsForStream(0, frame_events, packet_events,
+  if (!serializer.SerializeEventsForStream(false, frame_events, packet_events,
                                            first_rtp_timestamp)) {
     VLOG(1) << "Failed to serialize video events.";
     return;
@@ -367,8 +366,7 @@ void WriteLogsToFileAndStopSubscribing(
   VLOG(0) << "Audio frame map size: " << frame_events.size();
   VLOG(0) << "Audio packet map size: " << packet_events.size();
 
-  // "Assign" stream id 1 for the audio events.
-  if (!serializer.SerializeEventsForStream(1, frame_events, packet_events,
+  if (!serializer.SerializeEventsForStream(true, frame_events, packet_events,
                                            first_rtp_timestamp)) {
     VLOG(1) << "Failed to serialize audio events.";
     return;