Update VP8 settings to avoid spending bitrate on static areas. PERF NOTE

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 651406abf91d0c01f5eebaf7adb5bbe7d013e2ea..5714a07f2e38f5d8b5506047a8d55fc507b3dd63 100644
--- a/webrtc/modules/video_coding/codecs/vp8/vp8_impl.cc
+++ b/webrtc/modules/video_coding/codecs/vp8/vp8_impl.cc
@@ -664,7 +664,9 @@ int VP8EncoderImpl::InitAndSetControlSettings() {
                       denoiser_state : kDenoiserOff);
   }
   for (size_t i = 0; i < encoders_.size(); ++i) {
-    vpx_codec_control(&(encoders_[i]), VP8E_SET_STATIC_THRESHOLD, 1);
+    // Allow more screen content to be detected as static.
+    vpx_codec_control(&(encoders_[i]), VP8E_SET_STATIC_THRESHOLD,
+                      codec_.mode == kScreensharing ? 300 : 1);
     vpx_codec_control(&(encoders_[i]), VP8E_SET_CPUUSED, cpu_speed_[i]);
     vpx_codec_control(&(encoders_[i]), VP8E_SET_TOKEN_PARTITIONS,
                       static_cast<vp8e_token_partitions>(token_partitions_));