Reland of Periodically update codec bit/frame rate settings.

webrtc/modules/video_coding/media_optimization.cc

 /*
  *  Copyright (c) 2012 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.
  */
 
@@ skipping 100 matching lines @@
   video_target_bitrate_ = target_bitrate;
 
   // Cap target video bitrate to codec maximum.
   if (max_bit_rate_ > 0 && video_target_bitrate_ > max_bit_rate_) {
     video_target_bitrate_ = max_bit_rate_;
   }
 
   // Update encoding rates following protection settings.
   float target_video_bitrate_kbps =
       static_cast<float>(video_target_bitrate_) / 1000.0f;
-  frame_dropper_->SetRates(target_video_bitrate_kbps, incoming_frame_rate_);
+  float framerate = incoming_frame_rate_;
+  if (framerate == 0.0) {
+    // No framerate estimate available, use configured max framerate instead.
+    framerate = user_frame_rate_;
+  }
+
+  frame_dropper_->SetRates(target_video_bitrate_kbps, framerate);
 
   return video_target_bitrate_;
 }
 
 uint32_t MediaOptimization::InputFrameRate() {
   rtc::CritScope lock(&crit_sect_);
   return InputFrameRateInternal();
 }
 
 uint32_t MediaOptimization::InputFrameRateInternal() {
@@ skipping 140 matching lines @@
     const int64_t diff =
         incoming_frame_times_[0] - incoming_frame_times_[num - 1];
     incoming_frame_rate_ = 0.0;  // No frame rate estimate available.
     if (diff > 0) {
       incoming_frame_rate_ = nr_of_frames * 1000.0f / static_cast<float>(diff);
     }
   }
 }
 }  // namespace media_optimization
 }  // namespace webrtc