Add framerate to VideoSinkWants and ability to signal on overuse

webrtc/test/frame_generator_capturer.h

 /*
  *  Copyright (c) 2013 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 #ifndef WEBRTC_TEST_FRAME_GENERATOR_CAPTURER_H_
@@ skipping 69 matching lines @@
   Clock* const clock_;
   bool sending_;
   rtc::VideoSinkInterface<VideoFrame>* sink_ GUARDED_BY(&lock_);
   SinkWantsObserver* sink_wants_observer_ GUARDED_BY(&lock_);
 
   std::unique_ptr<EventTimerWrapper> tick_;
   rtc::CriticalSection lock_;
   rtc::PlatformThread thread_;
   std::unique_ptr<FrameGenerator> frame_generator_;
 
-  int target_fps_;
+  int target_fps_ GUARDED_BY(&lock_);
+  rtc::Optional<int> wanted_fps_ GUARDED_BY(&lock_);
   VideoRotation fake_rotation_ = kVideoRotation_0;
 
   int64_t first_frame_capture_time_;
 };
 }  // test
 }  // webrtc
 
 #endif  // WEBRTC_TEST_FRAME_GENERATOR_CAPTURER_H_