Reland of Drop frames until specified bitrate is achieved.

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 0c564724d4b96e49d9bc9d3e9718a3d0d93efde1..f4c3e6f53e854614b609f1bf2b46bf16d1db9ea1 100644
--- a/webrtc/video/vie_encoder.h
+++ b/webrtc/video/vie_encoder.h
@@ -150,6 +150,8 @@ class ViEEncoder : public rtc::VideoSinkInterface<VideoFrame>,
                                    bool nack_enabled);
   void ReconfigureEncoder();
 
+  void ConfigureQualityScaler();
+
   // Implements VideoSinkInterface.
   void OnFrame(const VideoFrame& video_frame) override;
 
@@ -175,6 +177,8 @@ class ViEEncoder : public rtc::VideoSinkInterface<VideoFrame>,
   rtc::Event shutdown_event_;
 
   const uint32_t number_of_cores_;
+  // Counts how many frames we've dropped in the initial rampup phase.
+  int initial_rampup_;
 
   const std::unique_ptr<VideoSourceProxy> source_proxy_;
   EncoderSink* sink_;