Removed SSRC knowledge from ViEEncoder.

webrtc/modules/video_coding/video_coding_impl.h

 /*
  *  Copyright (c) 2012 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 70 matching lines @@
                                uint8_t lossRate,
                                int64_t rtt);
 
   int32_t RegisterProtectionCallback(VCMProtectionCallback* protection);
   void SetVideoProtection(VCMVideoProtection videoProtection);
 
   int32_t AddVideoFrame(const VideoFrame& videoFrame,
                         const VideoContentMetrics* _contentMetrics,
                         const CodecSpecificInfo* codecSpecificInfo);
 
-  int32_t IntraFrameRequest(int stream_index);
+  int32_t IntraFrameRequest(size_t stream_index);
   int32_t EnableFrameDropper(bool enable);
 
   void SuspendBelowMinBitrate();
   bool VideoSuspended() const;
 
   int64_t TimeUntilNextProcess() override;
   void Process() override;
 
  private:
   void SetEncoderParameters(EncoderParameters params)
@@ skipping 109 matching lines @@
   VCMProcessTimer _receiveStatsTimer;
   VCMProcessTimer _retransmissionTimer;
   VCMProcessTimer _keyRequestTimer;
   QpParser qp_parser_;
   ThreadUnsafeOneTimeEvent first_frame_received_;
 };
 
 }  // namespace vcm
 }  // namespace webrtc
 #endif  // WEBRTC_MODULES_VIDEO_CODING_VIDEO_CODING_IMPL_H_