Extract bitrate allocation of spatial/temporal layers out of codec impl.

webrtc/modules/BUILD.gn

 # 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.
 
 import("../build/webrtc.gni")
 import("audio_coding/audio_coding.gni")
@@ skipping 471 matching lines @@
       "video_coding/nack_module_unittest.cc",
       "video_coding/percentile_filter_unittest.cc",
       "video_coding/protection_bitrate_calculator_unittest.cc",
       "video_coding/receiver_unittest.cc",
       "video_coding/rtp_frame_reference_finder_unittest.cc",
       "video_coding/sequence_number_util_unittest.cc",
       "video_coding/session_info_unittest.cc",
       "video_coding/test/stream_generator.cc",
       "video_coding/test/stream_generator.h",
       "video_coding/timing_unittest.cc",
+      "video_coding/utility/default_video_bitrate_allocator_unittest.cc",
       "video_coding/utility/frame_dropper_unittest.cc",
       "video_coding/utility/h264_bitstream_parser_unittest.cc",
       "video_coding/utility/ivf_file_writer_unittest.cc",
       "video_coding/utility/moving_average_unittest.cc",
       "video_coding/utility/quality_scaler_unittest.cc",
       "video_coding/utility/simulcast_rate_allocator_unittest.cc",
       "video_coding/video_coding_robustness_unittest.cc",
       "video_coding/video_packet_buffer_unittest.cc",
       "video_coding/video_receiver_unittest.cc",
       "video_coding/video_sender_unittest.cc",
@@ skipping 234 matching lines @@
       "../test:test_common",
       "../test:test_support_main",
       "remote_bitrate_estimator:bwe_simulator_lib",
       "video_capture",
       "//testing/gmock",
       "//testing/gtest",
       "//third_party/gflags",
     ]
   }
 }