Support delayed AudioUnit initialization.

webrtc/modules/audio_device/ios/audio_device_ios.h

 /*
  *  Copyright (c) 2012 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.
  */
 
@@ skipping 144 matching lines @@
   bool RecordingError() const override;
   void ClearPlayoutWarning() override {}
   void ClearPlayoutError() override {}
   void ClearRecordingWarning() override {}
   void ClearRecordingError() override {}
 
   // AudioSessionObserver methods. May be called from any thread.
   void OnInterruptionBegin() override;
   void OnInterruptionEnd() override;
   void OnValidRouteChange() override;
+  void OnConfiguredForWebRTC() override;
 
   // VoiceProcessingAudioUnitObserver methods.
   OSStatus OnDeliverRecordedData(AudioUnitRenderActionFlags* flags,
                                  const AudioTimeStamp* time_stamp,
                                  UInt32 bus_number,
                                  UInt32 num_frames,
                                  AudioBufferList* io_data) override;
   OSStatus OnGetPlayoutData(AudioUnitRenderActionFlags* flags,
                             const AudioTimeStamp* time_stamp,
                             UInt32 bus_number,
                             UInt32 num_frames,
                             AudioBufferList* io_data) override;
 
  private:
   // Called by the relevant AudioSessionObserver methods on |thread_|.
   void HandleInterruptionBegin();
   void HandleInterruptionEnd();
   void HandleValidRouteChange();
+  void HandleConfiguredForWebRTC();
 
   // Uses current |playout_parameters_| and |record_parameters_| to inform the
   // audio device buffer (ADB) about our internal audio parameters.
   void UpdateAudioDeviceBuffer();
 
   // Since the preferred audio parameters are only hints to the OS, the actual
   // values may be different once the AVAudioSession has been activated.
   // This method asks for the current hardware parameters and takes actions
   // if they should differ from what we have asked for initially. It also
   // defines |playout_parameters_| and |record_parameters_|.
@@ skipping 82 matching lines @@
   bool rec_is_initialized_;
 
   // Set to true after successful call to InitPlayout(), false otherwise.
   bool play_is_initialized_;
 
   // Set to true if audio session is interrupted, false otherwise.
   bool is_interrupted_;
 
   // Audio interruption observer instance.
   RTCAudioSessionDelegateAdapter* audio_session_observer_;
-
-  // Contains the audio data format specification for a stream of audio.
-  AudioStreamBasicDescription application_format_;
 };
 
 }  // namespace webrtc
 
 #endif  // WEBRTC_MODULES_AUDIO_DEVICE_IOS_AUDIO_DEVICE_IOS_H_