Refactor the AudioDevice for iOS and improve the performance and stability

webrtc/modules/audio_device/ios/audio_device_unittest_ios.cc

Index: webrtc/modules/audio_device/ios/audio_device_unittest_ios.cc
diff --git a/webrtc/modules/audio_device/ios/audio_device_unittest_ios.cc b/webrtc/modules/audio_device/ios/audio_device_unittest_ios.cc
index d4c4a4e235a08fd93c4a5934c8a666ba8c196953..b0e43718adc5a77d637875b3412aacbce77623a9 100644
--- a/webrtc/modules/audio_device/ios/audio_device_unittest_ios.cc
+++ b/webrtc/modules/audio_device/ios/audio_device_unittest_ios.cc
@@ -507,7 +507,6 @@ class AudioDeviceTest : public ::testing::Test {
     rtc::LogMessage::LogToDebug(old_sev_);
   }
 
-  // TODO(henrika): don't use hardcoded values below.
   int playout_sample_rate() const { return playout_parameters_.sample_rate(); }
   int record_sample_rate() const { return record_parameters_.sample_rate(); }
   int playout_channels() const { return playout_parameters_.channels(); }
@@ -519,11 +518,6 @@ class AudioDeviceTest : public ::testing::Test {
     return record_parameters_.frames_per_10ms_buffer();
   }
 
-  int total_delay_ms() const {
-    // TODO(henrika): improve this part.
-    return 100;
-  }
-
   rtc::scoped_refptr<AudioDeviceModule> audio_device() const {
     return audio_device_;
   }