Set min BWE bitrate form 10kbps to 5kbps and centralize minimum bitrate.

webrtc/modules/congestion_controller/include/defines.h

 /*
  *  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.
  */
 
-#include "webrtc/modules/audio_coding/neteq/packet.h"
+#ifndef WEBRTC_MODULES_CONGESTION_CONTROLLER_INCLUDE_DEFINES_H_
+#define WEBRTC_MODULES_CONGESTION_CONTROLLER_INCLUDE_DEFINES_H_
 
 namespace webrtc {
+namespace congestion_controller {
+constexpr int kMinBitrateBps = 5000;

[stefan-webrtc, 2016/10/31 08:58:57]

I think we should put this behind a field trial too. Maybe:

int GetMinBitrateBps() {
  if (webrtc::field_trial::FindFullName("WebRTC-Audio-SendSideBwe") ==
      "Enabled") {
    return kAudioMinBitrateBps;  // 5 kbps.
  }
  return kMinBitrateBps;  // 10 kbps.
}

That way this impact the BWE behavior until we are sure things work well after
experimenting.


WDYT? Minyue?

[michaelt, 2016/10/31 11:09:09]

Sounds fine to me. 
I had to move the impl. of the function to congestion_controller.cc other wise
we would have linker errors. 

Done

+}  // namespace congestion_controller
+}  // namespace webrtc
 
-Packet::Packet() = default;
-
-Packet::~Packet() = default;
-
-}  // namespace webrtc
+#endif  // WEBRTC_MODULES_CONGESTION_CONTROLLER_INCLUDE_DEFINES_H_