[Remoting Host] Supporting WebRTC VP9 streaming

remoting/protocol/webrtc_transport.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "remoting/protocol/webrtc_transport.h"
 
 #include <string>
 #include <utility>
 #include <vector>
 
@@ skipping 53 matching lines @@
   //  - Setting min bitrate here enables padding.
   //  - The default max bitrate is 600 kbps. Setting it to 100 Mbps allows to
   //    use higher bandwidth when it's available.
   //
   // TODO(sergeyu): Padding needs to be enabled to workaround BW estimator not
   // handling spiky traffic patterns well. This won't be necessary with a
   // better bandwidth estimator.
   // TODO(isheriff): The need for this should go away once we have a proper
   // API to provide max bitrate for the case of handing over encoded
   // frames to webrtc.
-  if (sdp_message->has_video() &&
-      !sdp_message->AddCodecParameter(
-          "VP8", "x-google-min-bitrate=1000; x-google-max-bitrate=100000")) {
-    if (incoming) {
-      LOG(WARNING) << "VP8 not found in an incoming SDP.";
-    } else {
-      LOG(FATAL) << "VP8 not found in SDP generated by WebRTC.";
+  if (sdp_message->has_video()) {
+    bool param_added = sdp_message->AddCodecParameter(
+        "VP8", "x-google-min-bitrate=1000; x-google-max-bitrate=100000");
+    param_added |= sdp_message->AddCodecParameter(
+        "VP9", "x-google-min-bitrate=1000; x-google-max-bitrate=100000");
+    if (!param_added) {
+      if (incoming) {
+        LOG(WARNING) << "Neither of VP8/VP9 is found in an incoming SDP.";
+      } else {
+        LOG(FATAL) << "Neither of VP8/VP9 is found in SDP generated by WebRTC.";
+      }
     }
   }
 
   // Update SDP format to use 160kbps stereo for opus codec.
   if (sdp_message->has_audio() &&
       !sdp_message->AddCodecParameter("opus",
                                       "stereo=1; maxaveragebitrate=163840")) {
     if (incoming) {
       LOG(WARNING) << "Opus not found in an incoming SDP.";
     } else {
@@ skipping 623 matching lines @@
   // the stack and so it must be destroyed later.
   base::ThreadTaskRunnerHandle::Get()->DeleteSoon(
       FROM_HERE, peer_connection_wrapper_.release());
 
   if (error != OK)
     event_handler_->OnWebrtcTransportError(error);
 }
 
 }  // namespace protocol
 }  // namespace remoting