Instantly pass network changes to controllers in audio network adaptor.

webrtc/modules/audio_coding/audio_network_adaptor/bitrate_controller.cc

 /*
  *  Copyright (c) 2016 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 15 matching lines @@
 BitrateController::Config::~Config() = default;
 
 BitrateController::BitrateController(const Config& config)
     : config_(config),
       bitrate_bps_(config_.initial_bitrate_bps),
       frame_length_ms_(config_.initial_frame_length_ms) {
   RTC_DCHECK_GT(bitrate_bps_, 0);
   RTC_DCHECK_GT(frame_length_ms_, 0);
 }
 
+BitrateController::~BitrateController() = default;
+
+void BitrateController::UpdateNetworkMetrics(
+    const NetworkMetrics& network_metrics) {
+  if (network_metrics.target_audio_bitrate_bps)
+    target_audio_bitrate_bps_ = network_metrics.target_audio_bitrate_bps;
+  if (network_metrics.overhead_bytes_per_packet)
+    overhead_bytes_per_packet_ = network_metrics.overhead_bytes_per_packet;
+}
+
 void BitrateController::MakeDecision(
-    const NetworkMetrics& metrics,
     AudioNetworkAdaptor::EncoderRuntimeConfig* config) {
   // Decision on |bitrate_bps| should not have been made.
   RTC_DCHECK(!config->bitrate_bps);
-  if (metrics.target_audio_bitrate_bps && metrics.overhead_bytes_per_packet) {
+  if (target_audio_bitrate_bps_ && overhead_bytes_per_packet_) {
     // Current implementation of BitrateController can only work when
     // |metrics.target_audio_bitrate_bps| includes overhead is enabled. This is
     // currently governed by the following field trial.
     RTC_DCHECK_EQ("Enabled", webrtc::field_trial::FindFullName(
                                  "WebRTC-SendSideBwe-WithOverhead"));
     if (config->frame_length_ms)
       frame_length_ms_ = *config->frame_length_ms;
     int overhead_rate_bps =
-        *metrics.overhead_bytes_per_packet * 8 * 1000 / frame_length_ms_;
-    bitrate_bps_ =
-        std::max(0, *metrics.target_audio_bitrate_bps - overhead_rate_bps);
+        *overhead_bytes_per_packet_ * 8 * 1000 / frame_length_ms_;
+    bitrate_bps_ = std::max(0, *target_audio_bitrate_bps_ - overhead_rate_bps);
   }
   config->bitrate_bps = rtc::Optional<int>(bitrate_bps_);
 }
 
 }  // namespace audio_network_adaptor
 }  // namespace webrtc