Switch browser side audio capture path to use base time primitives.

media/audio/mac/audio_low_latency_input_mac.h

 // Copyright (c) 2012 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.
 //
 // Implementation of AudioInputStream for Mac OS X using the special AUHAL
 // input Audio Unit present in OS 10.4 and later.
 // The AUHAL input Audio Unit is for low-latency audio I/O.
 //
 // Overview of operation:
 //
@@ skipping 122 matching lines @@
   void UpdateDataCallbackTimeOnMainThread(base::TimeTicks now_tick);
 
   // Registers OnDevicePropertyChanged() to receive notifications when device
   // properties changes.
   void RegisterDeviceChangeListener();
   // Stop listening for changes in device properties.
   void DeRegisterDeviceChangeListener();
 
   // Gets the fixed capture hardware latency and store it during initialization.
   // Returns 0 if not available.
-  double GetHardwareLatency();
+  base::TimeDelta GetHardwareLatency();
 
   // Gets the current capture delay value.
-  double GetCaptureLatency(const AudioTimeStamp* input_time_stamp);
+  base::TimeDelta GetCaptureLatency(const AudioTimeStamp* input_time_stamp);
 
   // Gets the number of channels for a stream of audio data.
   int GetNumberOfChannelsFromStream();
 
   // Issues the OnError() callback to the |sink_|.
   void HandleError(OSStatus err);
 
   // Helper function to check if the volume control is avialable on specific
   // channel.
   bool IsVolumeSettableOnChannel(int channel);
@@ skipping 68 matching lines @@
   // The UID refers to the current input audio device.
   const AudioDeviceID input_device_id_;
 
   // Provides a mechanism for encapsulating one or more buffers of audio data.
   AudioBufferList audio_buffer_list_;
 
   // Temporary storage for recorded data. The InputProc() renders into this
   // array as soon as a frame of the desired buffer size has been recorded.
   std::unique_ptr<uint8_t[]> audio_data_buffer_;
 
-  // Fixed capture hardware latency in frames.
-  double hardware_latency_frames_;
+  // Fixed capture hardware latency.
+  base::TimeDelta hardware_latency_;
 
   // The number of channels in each frame of audio data, which is used
   // when querying the volume of each channel.
   int number_of_channels_in_frame_;
 
   // FIFO used to accumulates recorded data.
   media::AudioBlockFifo fifo_;
 
   // Used to defer Start() to workaround http://crbug.com/160920.
   base::CancelableClosure deferred_start_cb_;
@@ skipping 84 matching lines @@
   // this object is destroyed.
   // Note that, all member variables should appear before the WeakPtrFactory.
   base::WeakPtrFactory<AUAudioInputStream> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(AUAudioInputStream);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_AUDIO_MAC_AUDIO_LOW_LATENCY_INPUT_MAC_H_