Remove RTCVideoEncoder::SetChannelParameters function.

Cleanup related to https://webrtc-review.googlesource.com/c/src/+/108861

Bug: webrtc:9946
Change-Id: Iae472e30fa5e574c7e23b53c5dc7af767838b98f
Reviewed-on: https://chromium-review.googlesource.com/c/1323091Reviewed-by: Florent Castelli <orphis@chromium.org>
Commit-Queue: Philip Eliasson <philipel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#606403}

content/renderer/media/webrtc/rtc_video_encoder.cc

@@ -938,13 +938,6 @@ int32_t RTCVideoEncoder::Release() {
   return WEBRTC_VIDEO_CODEC_OK;
 }
 
-int32_t RTCVideoEncoder::SetChannelParameters(uint32_t packet_loss,
-                                              int64_t rtt) {
-  DVLOG(3) << __func__ << " packet_loss=" << packet_loss << ", rtt=" << rtt;
-  // Ignored.
-  return WEBRTC_VIDEO_CODEC_OK;
-}
-
 int32_t RTCVideoEncoder::SetRateAllocation(
     const webrtc::VideoBitrateAllocation& allocation,
     uint32_t frame_rate) {

content/renderer/media/webrtc/rtc_video_encoder.h

@@ -57,7 +57,6 @@ class CONTENT_EXPORT RTCVideoEncoder : public webrtc::VideoEncoder {
   int32_t RegisterEncodeCompleteCallback(
       webrtc::EncodedImageCallback* callback) override;
   int32_t Release() override;
-  int32_t SetChannelParameters(uint32_t packet_loss, int64_t rtt) override;
   int32_t SetRateAllocation(const webrtc::VideoBitrateAllocation& allocation,
                             uint32_t framerate) override;
   bool SupportsNativeHandle() const override;