Ability to disable the effects of |rtc_use_h264| with DisableRtcUseH264.

webrtc/modules/video_coding/codecs/h264/include/h264.h

Index: webrtc/modules/video_coding/codecs/h264/include/h264.h
diff --git a/webrtc/modules/video_coding/codecs/h264/include/h264.h b/webrtc/modules/video_coding/codecs/h264/include/h264.h
index 7f0bbf042beddc0f091fa2779e7789a732dccead..9695f684983c7a547f7049b1d0237b49199249ce 100644
--- a/webrtc/modules/video_coding/codecs/h264/include/h264.h
+++ b/webrtc/modules/video_coding/codecs/h264/include/h264.h
@@ -27,6 +27,12 @@
 
 namespace webrtc {
 
+// Set to enable or disable the H.264 encoder/decoder implementations that are
+// provided if |rtc_use_h264| build flag is true (if false, this function does
+// nothing). This function should only be called before or during WebRTC
+// initialization and is not thread-safe.

[tommi, 2016/02/02 16:33:13]

ah, not thread safe. Good comment.  Feel free to ignore my tsan comment.

[hbos, 2016/02/02 17:08:19]

Acknowledged.

+void SetRtcUseH264(bool enable);
+
 class H264Encoder : public VideoEncoder {
  public:
   static H264Encoder* Create();