Expose codec implementation names in stats.

webrtc/video/video_decoder.cc

 /*
  *  Copyright (c) 2015 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 113 matching lines @@
     fallback_decoder_->Release();
   return decoder_->Release();
 }
 
 int32_t VideoDecoderSoftwareFallbackWrapper::Reset() {
   if (fallback_decoder_)
     fallback_decoder_->Reset();
   return decoder_->Reset();
 }
 
+const char* VideoDecoderSoftwareFallbackWrapper::ImplementationName() const {
+  if (fallback_decoder_)
+    return fallback_decoder_->ImplementationName();
+  return decoder_->ImplementationName();
+}
+
 }  // namespace webrtc