Expose codec implementation names in stats.

webrtc/video_encoder.h

Index: webrtc/video_encoder.h
diff --git a/webrtc/video_encoder.h b/webrtc/video_encoder.h
index f255336a25a0c4d7f5e082882d9d218522e53b45..9e7e4d7040f2fd8401ac934144619612f5fe750a 100644
--- a/webrtc/video_encoder.h
+++ b/webrtc/video_encoder.h
@@ -11,6 +11,7 @@
 #ifndef WEBRTC_VIDEO_ENCODER_H_
 #define WEBRTC_VIDEO_ENCODER_H_
 
+#include <string>
 #include <vector>
 
 #include "webrtc/common_types.h"
@@ -124,6 +125,7 @@ class VideoEncoder {
   virtual void OnDroppedFrame() {}
   virtual int GetTargetFramerate() { return -1; }
   virtual bool SupportsNativeHandle() const { return false; }
+  virtual const char* ImplementationName() const { return "unknown"; }
 };
 
 // Class used to wrap external VideoEncoders to provide a fallback option on
@@ -151,6 +153,7 @@ class VideoEncoderSoftwareFallbackWrapper : public VideoEncoder {
   void OnDroppedFrame() override;
   int GetTargetFramerate() override;
   bool SupportsNativeHandle() const override;
+  const char* ImplementationName() const override;
 
  private:
   bool InitFallbackEncoder();
@@ -175,6 +178,7 @@ class VideoEncoderSoftwareFallbackWrapper : public VideoEncoder {
   webrtc::VideoEncoder* const encoder_;
 
   rtc::scoped_ptr<webrtc::VideoEncoder> fallback_encoder_;
+  std::string fallback_implementation_name_;
   EncodedImageCallback* callback_;
 };
 }  // namespace webrtc