Fix when SetMinimumPlayoutDelay is configured to 0

BUG=1720
R=turaj@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/1386005

git-svn-id: http://webrtc.googlecode.com/svn/trunk@3942 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/webrtc/modules/audio_coding/main/source/audio_coding_module_impl.cc b/webrtc/modules/audio_coding/main/source/audio_coding_module_impl.cc
index a0cde49..be9befc 100644
--- a/webrtc/modules/audio_coding/main/source/audio_coding_module_impl.cc
+++ b/webrtc/modules/audio_coding/main/source/audio_coding_module_impl.cc
@@ -2932,7 +2932,9 @@
     return -1;
   }
   initial_delay_ms_ = delay_ms;
-  track_neteq_buffer_ = true;
+  if (delay_ms > 0) {
+    track_neteq_buffer_ = true;
+  }
   av_sync_ = true;
   neteq_.EnableAVSync(av_sync_);
   return neteq_.SetExtraDelay(delay_ms);
@@ -2946,6 +2948,7 @@
   }
 
   if (accumulated_audio_ms_ >= initial_delay_ms_) {
+    // We have enough data stored that match our initial delay target.
     track_neteq_buffer_ = false;
     return false;
   }