Add initial bitrate and frame resolution parameters to quality scaler.

webrtc/modules/video_coding/codecs/vp8/vp8_impl.cc

Index: webrtc/modules/video_coding/codecs/vp8/vp8_impl.cc
diff --git a/webrtc/modules/video_coding/codecs/vp8/vp8_impl.cc b/webrtc/modules/video_coding/codecs/vp8/vp8_impl.cc
index 5d22d72144413f0cb6477cdc38db082b1c272b5c..eac0afd983fe35c57e2e358a059795f8256d9daa 100644
--- a/webrtc/modules/video_coding/codecs/vp8/vp8_impl.cc
+++ b/webrtc/modules/video_coding/codecs/vp8/vp8_impl.cc
@@ -600,8 +600,10 @@ int VP8EncoderImpl::InitEncode(const VideoCodec* inst,
   // Disable both high-QP limits and framedropping. Both are handled by libvpx
   // internally.
   const int kDisabledBadQpThreshold = 64;
+  // TODO(glaznev/sprang): consider passing codec initial bitrate to quality
+  // scaler to avoid starting with HD for low initial bitrates.
   quality_scaler_.Init(codec_.qpMax / QualityScaler::kDefaultLowQpDenominator,
-                       kDisabledBadQpThreshold, false);
+                       kDisabledBadQpThreshold, false, 0, 0, 0);
   quality_scaler_.ReportFramerate(codec_.maxFramerate);
 
   // Only apply scaling to improve for single-layer streams. The scaling metrics