Revert of Pass task runners to AudioManager constructor.

components/audio_modem/audio_recorder_impl.h

 // Copyright 2015 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 COMPONENTS_AUDIO_MODEM_AUDIO_RECORDER_IMPL_H_
 #define COMPONENTS_AUDIO_MODEM_AUDIO_RECORDER_IMPL_H_
 
 #include <stdint.h>
 
 #include <string>
@@ skipping 61 matching lines @@
   // AudioInputStream::AudioInputCallback overrides:
   // Called by the audio recorder when a full packet of audio data is
   // available. This is called from a special audio thread and the
   // implementation should return as soon as possible.
   void OnData(media::AudioInputStream* stream,
               const media::AudioBus* source,
               uint32_t hardware_delay_bytes,
               double volume) override;
   void OnError(media::AudioInputStream* stream) override;
 
+  // Flushes the audio loop, making sure that any queued operations are
+  // performed.
+  void FlushAudioLoopForTesting();
+
   bool is_recording_;
 
   media::AudioInputStream* stream_;
 
   RecordedSamplesCallback decode_callback_;
 
   // Outside of the ctor/Initialize method, only access the next variables on
   // the recording thread.
   scoped_ptr<media::AudioBus> buffer_;
   int total_buffer_frames_;
   int buffer_frame_index_;
 
   scoped_ptr<media::AudioInputStream> input_stream_for_testing_;
   scoped_ptr<media::AudioParameters> params_for_testing_;
 
   DISALLOW_COPY_AND_ASSIGN(AudioRecorderImpl);
 };
 
 }  // namespace audio_modem
 
 #endif  // COMPONENTS_AUDIO_MODEM_AUDIO_RECORDER_IMPL_H_