[Cast] Remove AudioDecoder's dependency on WebRTC, and refactor/clean-up AudioReceiver.

media/cast/test/utility/audio_utility.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef MEDIA_CAST_TEST_UTILITY_AUDIO_UTILITY_H_
 #define MEDIA_CAST_TEST_UTILITY_AUDIO_UTILITY_H_
 
 #include "media/audio/simple_sources.h"
 
 namespace base {
@@ skipping 38 matching lines @@
 // Convenience function to convert an |audio_bus| to its equivalent
 // PcmAudioFrame.
 // TODO(miu): Remove this once all code has migrated to use AudioBus.  See
 // comment in media/cast/cast_config.h.
 scoped_ptr<PcmAudioFrame> ToPcmAudioFrame(const AudioBus& audio_bus,
                                           int sample_rate);
 
 // Assuming |samples| contains a single-frequency sine wave (and maybe some
 // low-amplitude noise), count the number of times the sine wave crosses
 // zero.
+int CountZeroCrossings(const float* samples, int len);
+// DEPRECATED:
 int CountZeroCrossings(const std::vector<int16>& samples);
 
 // Encode |timestamp| into the samples pointed to by 'samples' in a way
 // that should be decodable even after compressing/decompressing the audio.
 // Assumes 48Khz sampling rate and needs at least 240 samples. Returns
 // false if |samples| is too small. If more than 240 samples are available,
 // then the timestamp will be repeated. |sample_offset| should contain how
 // many samples has been encoded so far, so that we can make smooth
 // transitions between encoded chunks.
 // See audio_utility.cc for details on how the encoding is done.
 bool EncodeTimestamp(uint16 timestamp,
                      size_t sample_offset,
                      std::vector<int16>* samples);
 
 // Decode a timestamp encoded with EncodeTimestamp. Returns true if a
 // timestamp was found in |samples|.
 bool DecodeTimestamp(const std::vector<int16>& samples, uint16* timestamp);
 
 }  // namespace cast
 }  // namespace media
 
 #endif  // MEDIA_CAST_TEST_UTILITY_AUDIO_UTILITY_H_