Initialize VideoEncoder objects asynchronously.

webrtc/video/vie_encoder.h

Index: webrtc/video/vie_encoder.h
diff --git a/webrtc/video/vie_encoder.h b/webrtc/video/vie_encoder.h
index a7452f7da89b6b5ee37da5776d0128107d34f62f..52f4e8900a621ad9db4e2fea866ae034cd41bc9a 100644
--- a/webrtc/video/vie_encoder.h
+++ b/webrtc/video/vie_encoder.h
@@ -82,11 +82,7 @@ class ViEEncoder : public RtcpIntraFrameObserver,
   void Restart();
 
   // Codec settings.
-  int32_t RegisterExternalEncoder(VideoEncoder* encoder,
-                                  uint8_t pl_type,
-                                  bool internal_source);
-  int32_t DeRegisterExternalEncoder(uint8_t pl_type);
-  int32_t SetEncoder(const VideoCodec& video_codec);
+  void SetEncoder(const VideoCodec& video_codec);
 
   // Implementing VideoCaptureCallback.
   void DeliverFrame(VideoFrame video_frame) override;
@@ -129,16 +125,12 @@ class ViEEncoder : public RtcpIntraFrameObserver,
 
   void SetMinTransmitBitrate(int min_transmit_bitrate_kbps);
 
-  // Lets the sender suspend video when the rate drops below
-  // |threshold_bps|, and turns back on when the rate goes back up above
-  // |threshold_bps| + |window_bps|.
-  void SuspendBelowMinBitrate();
-
   // New-style callbacks, used by VideoSendStream.
   void RegisterPostEncodeImageCallback(
         EncodedImageCallback* post_encode_callback);
 
   int GetPaddingNeededBps() const;
+  VideoCodingModule* vcm() const;
 
  protected:
   // Called by BitrateObserver.