Add VP9 encode support to the remoting host.

remoting/host/client_session.cc

Index: remoting/host/client_session.cc
diff --git a/remoting/host/client_session.cc b/remoting/host/client_session.cc
index 52feba70462efae8bc4d28cce9f9f09cd605d073..5ef9737230f8cf3419ca3f4763bec2bffa24e43b 100644
--- a/remoting/host/client_session.cc
+++ b/remoting/host/client_session.cc
@@ -429,6 +429,8 @@ scoped_ptr<VideoEncoder> ClientSession::CreateVideoEncoder(
 
   if (video_config.codec == protocol::ChannelConfig::CODEC_VP8) {
     return remoting::VideoEncoderVpx::CreateForVP8().PassAs<VideoEncoder>();
+  } else if (video_config.codec == protocol::ChannelConfig::CODEC_VP9) {
+    return remoting::VideoEncoderVpx::CreateForVP9().PassAs<VideoEncoder>();
   }
 
   NOTREACHED();