Move usage of QualityScaler to ViEEncoder.

webrtc/sdk/objc/Framework/Classes/h264_video_toolbox_encoder.h

Index: webrtc/sdk/objc/Framework/Classes/h264_video_toolbox_encoder.h
diff --git a/webrtc/sdk/objc/Framework/Classes/h264_video_toolbox_encoder.h b/webrtc/sdk/objc/Framework/Classes/h264_video_toolbox_encoder.h
index 3acdf641cdfea4e28646ccfb82282584779c9888..4c9c590603f5917cd88f4199469a6befa8c82170 100644
--- a/webrtc/sdk/objc/Framework/Classes/h264_video_toolbox_encoder.h
+++ b/webrtc/sdk/objc/Framework/Classes/h264_video_toolbox_encoder.h
@@ -45,7 +45,6 @@ class H264VideoToolboxEncoder : public H264Encoder {
 
   int RegisterEncodeCompleteCallback(EncodedImageCallback* callback) override;
 
-  void OnDroppedFrame() override;
   int SetChannelParameters(uint32_t packet_loss, int64_t rtt) override;
 
   int SetRates(uint32_t new_bitrate_kbit, uint32_t frame_rate) override;
@@ -66,6 +65,8 @@ class H264VideoToolboxEncoder : public H264Encoder {
                       uint32_t timestamp,
                       VideoRotation rotation);
 
+  QualityScaler::Settings GetQPThresholds() const override;
+
  private:
   int ResetCompressionSession();
   void ConfigureCompressionSession();
@@ -83,10 +84,7 @@ class H264VideoToolboxEncoder : public H264Encoder {
   int32_t width_;
   int32_t height_;
 
-  rtc::CriticalSection quality_scaler_crit_;
-  QualityScaler quality_scaler_ GUARDED_BY(quality_scaler_crit_);
   H264BitstreamParser h264_bitstream_parser_;
-  bool enable_scaling_;
   std::vector<uint8_t> nv12_scale_buffer_;
 };  // H264VideoToolboxEncoder