Let CreateVideoDecoder take a cricket::VideoCodec.

webrtc/media/engine/webrtcvideoengine.cc

Index: webrtc/media/engine/webrtcvideoengine.cc
diff --git a/webrtc/media/engine/webrtcvideoengine.cc b/webrtc/media/engine/webrtcvideoengine.cc
index 6808f2c59afedc7d468b9326cc3350510244206a..eb5fa1d247812dbb30a16c084719c8aef80ea0ff 100644
--- a/webrtc/media/engine/webrtcvideoengine.cc
+++ b/webrtc/media/engine/webrtcvideoengine.cc
@@ -2188,7 +2188,7 @@ WebRtcVideoChannel::WebRtcVideoReceiveStream::CreateOrReuseVideoDecoder(
   if (external_decoder_factory_ != NULL) {
     webrtc::VideoDecoder* decoder =
         external_decoder_factory_->CreateVideoDecoderWithParams(
-            type, {stream_params_.id});
+            codec, {stream_params_.id});
     if (decoder != NULL) {
       return AllocatedDecoder(decoder, type, true /* is_external */);
     }
@@ -2196,7 +2196,7 @@ WebRtcVideoChannel::WebRtcVideoReceiveStream::CreateOrReuseVideoDecoder(
 
   InternalDecoderFactory internal_decoder_factory;
   return AllocatedDecoder(internal_decoder_factory.CreateVideoDecoderWithParams(
-                              type, {stream_params_.id}),
+                              codec, {stream_params_.id}),
                           type, false /* is_external */);
 }