Relanding of "Adding BitrateController to audio network adaptor."

webrtc/modules/audio_coding/BUILD.gn

 # Copyright (c) 2014 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.
 
 import("../../build/webrtc.gni")
 import("audio_coding.gni")
@@ skipping 683 matching lines @@
   } else if (build_with_mozilla) {
     include_dirs = [ getenv("DIST") + "/include/opus" ]
   }
 }
 
 source_set("audio_network_adaptor") {
   sources = [
     "audio_network_adaptor/audio_network_adaptor.cc",
     "audio_network_adaptor/audio_network_adaptor_impl.cc",
     "audio_network_adaptor/audio_network_adaptor_impl.h",
+    "audio_network_adaptor/bitrate_controller.cc",
+    "audio_network_adaptor/bitrate_controller.h",
     "audio_network_adaptor/channel_controller.cc",
     "audio_network_adaptor/channel_controller.h",
     "audio_network_adaptor/controller.cc",
     "audio_network_adaptor/controller.h",
     "audio_network_adaptor/controller_manager.cc",
     "audio_network_adaptor/controller_manager.h",
     "audio_network_adaptor/dtx_controller.cc",
     "audio_network_adaptor/dtx_controller.h",
     "audio_network_adaptor/frame_length_controller.cc",
     "audio_network_adaptor/frame_length_controller.h",
@@ skipping 855 matching lines @@
       "//testing/gtest",
     ]
 
     if (is_clang) {
       # Suppress warnings from Chrome's Clang plugins.
       # See http://code.google.com/p/webrtc/issues/detail?id=163 for details.
       suppressed_configs += [ "//build/config/clang:find_bad_constructs" ]
     }
   }
 }