Style changes in Audio Mixer

webrtc/modules/audio_mixer/test/audio_mixer_unittest.cc

 /*
  *  Copyright (c) 2016 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 269 matching lines @@
   }
 }
 
 TEST(AudioMixer, ParticipantNumberOfChannels) {
   const std::unique_ptr<AudioMixer> mixer(AudioMixer::Create(kId));
 
   MockMixerAudioSource participant;
   ResetFrame(participant.fake_frame());
 
   EXPECT_EQ(0, mixer->SetMixabilityStatus(&participant, true));
-  for (size_t number_of_channels : {1, 2}) {
+  for (int number_of_channels : {1, 2}) {
     EXPECT_CALL(participant, GetAudioFrameWithMuted(_, kDefaultSampleRateHz))
         .Times(Exactly(1));
     mixer->Mix(kDefaultSampleRateHz, number_of_channels, &frame_for_mixing);
-    EXPECT_EQ(number_of_channels, frame_for_mixing.num_channels_);
+    EXPECT_EQ(static_cast<size_t>(number_of_channels),

[ossu, 2016/09/05 12:02:54]

I believe you should be able to use one of int or size_t throughout AudioMixer.
There should be no reason to cast between them unless you need to interface with
something external that is outside of your control (at least right now, in these
CLs). I believe I prefer size_t throughout for channel counts.

+              frame_for_mixing.num_channels_);
   }
 }
 
 // Test that the volume is reported as zero when the mixer input
 // comprises only zero values.
 TEST(AudioMixer, LevelIsZeroWhenMixingZeroes) {
   const std::unique_ptr<AudioMixer> mixer(AudioMixer::Create(kId));
 
   MockMixerAudioSource participant;
   ResetFrame(participant.fake_frame());
@@ skipping 194 matching lines @@
       kAudioSources, MixerAudioSource::AudioFrameInfo::kNormal);
   frame_info[0] = MixerAudioSource::AudioFrameInfo::kMuted;
   std::fill(frames[0].data_, frames[0].data_ + kDefaultSampleRateHz / 100,
             std::numeric_limits<int16_t>::max());
   std::vector<bool> expected_status(kAudioSources, true);
   expected_status[0] = false;
 
   MixAndCompare(frames, frame_info, expected_status);
 }
 }  // namespace webrtc