Remove ignored return code from modules.

webrtc/modules/audio_conference_mixer/source/audio_conference_mixer_impl.cc

Index: webrtc/modules/audio_conference_mixer/source/audio_conference_mixer_impl.cc
diff --git a/webrtc/modules/audio_conference_mixer/source/audio_conference_mixer_impl.cc b/webrtc/modules/audio_conference_mixer/source/audio_conference_mixer_impl.cc
index 9411a9a47e4892e3595b8aedcfe03875799a2ddb..1d7602533e483765d697dd463461422beef1a50d 100644
--- a/webrtc/modules/audio_conference_mixer/source/audio_conference_mixer_impl.cc
+++ b/webrtc/modules/audio_conference_mixer/source/audio_conference_mixer_impl.cc
@@ -189,7 +189,7 @@ int64_t AudioConferenceMixerImpl::TimeUntilNextProcess() {
     return timeUntilNextProcess;
 }
 
-int32_t AudioConferenceMixerImpl::Process() {
+void AudioConferenceMixerImpl::Process() {
     size_t remainingParticipantsAllowedToMix =
         kMaximumAmountOfMixedParticipants;
     {
@@ -222,7 +222,7 @@ int32_t AudioConferenceMixerImpl::Process() {
         if(lowFreq <= 0) {
             CriticalSectionScoped cs(_crit.get());
             _processCalls--;
-            return 0;
+            return;
         } else {
             switch(lowFreq) {
             case 8000:
@@ -250,7 +250,7 @@ int32_t AudioConferenceMixerImpl::Process() {
 
                 CriticalSectionScoped cs(_crit.get());
                 _processCalls--;
-                return -1;
+                return;
             }
         }
 
@@ -267,10 +267,9 @@ int32_t AudioConferenceMixerImpl::Process() {
         WEBRTC_TRACE(kTraceMemory, kTraceAudioMixerServer, _id,
                      "failed PopMemory() call");
         assert(false);
-        return -1;
+        return;
     }
 
-    int retval = 0;
     {
         CriticalSectionScoped cs(_crit.get());
 
@@ -304,8 +303,7 @@ int32_t AudioConferenceMixerImpl::Process() {
             mixedAudio->Mute();
         } else {
             // Only call the limiter if we have something to mix.
-            if(!LimitMixedAudio(mixedAudio))
-                retval = -1;
+            LimitMixedAudio(mixedAudio);
         }
     }
 
@@ -330,7 +328,7 @@ int32_t AudioConferenceMixerImpl::Process() {
         CriticalSectionScoped cs(_crit.get());
         _processCalls--;
     }
-    return retval;
+    return;
 }
 
 int32_t AudioConferenceMixerImpl::RegisterMixedStreamCallback(