Changed the interface AudioMixer::RemoveSource to have a void return type.

webrtc/modules/audio_mixer/audio_mixer_impl.cc

Index: webrtc/modules/audio_mixer/audio_mixer_impl.cc
diff --git a/webrtc/modules/audio_mixer/audio_mixer_impl.cc b/webrtc/modules/audio_mixer/audio_mixer_impl.cc
index d7025f9e671279fc73bd7152f55663228c8a005a..4bd96cd72f5a72657a80c0f2639f726dec294758 100644
--- a/webrtc/modules/audio_mixer/audio_mixer_impl.cc
+++ b/webrtc/modules/audio_mixer/audio_mixer_impl.cc
@@ -280,13 +280,12 @@ bool AudioMixerImpl::AddSource(Source* audio_source) {
   return true;
 }
 
-bool AudioMixerImpl::RemoveSource(Source* audio_source) {
+void AudioMixerImpl::RemoveSource(Source* audio_source) {
   RTC_DCHECK(audio_source);
   rtc::CritScope lock(&crit_);
   const auto iter = FindSourceInList(audio_source, &audio_source_list_);
   RTC_DCHECK(iter != audio_source_list_.end()) << "Source not present in mixer";
   audio_source_list_.erase(iter);
-  return true;
 }
 
 AudioFrameList AudioMixerImpl::GetAudioFromSources() {