Add framerate to VideoSinkWants and ability to signal on overuse

webrtc/call/bitrate_estimator_tests.cc

Index: webrtc/call/bitrate_estimator_tests.cc
diff --git a/webrtc/call/bitrate_estimator_tests.cc b/webrtc/call/bitrate_estimator_tests.cc
index bb4960f658efbe2ef919032a5cfe9cc17aac7498..24874eb78809a682b2fce2679366301818a12af9 100644
--- a/webrtc/call/bitrate_estimator_tests.cc
+++ b/webrtc/call/bitrate_estimator_tests.cc
@@ -172,7 +172,7 @@ class BitrateEstimatorTest : public test::CallTest {
           Clock::GetRealTimeClock()));
       send_stream_->SetSource(
           frame_generator_capturer_.get(),
-          VideoSendStream::DegradationPreference::kBalanced);
+          VideoSendStream::DegradationPreference::kMaintainFramerate);

[stefan-webrtc, 2017/03/21 15:37:36]

Isn't balanced a better default, or why do we change it?

[sprang_webrtc, 2017/03/21 15:59:18]

Balanced was never balanced. It was maintain-framerate (ie scale down on overuse
detection). I've thus renamed it everywhere. When we introduce a balanced mode
we will probably want to evaluate it before making it the default.

       send_stream_->Start();
       frame_generator_capturer_->Start();