Add UMA stats for AEC filter divergence metric.

content/renderer/media/media_stream_audio_processor.cc

Index: content/renderer/media/media_stream_audio_processor.cc
diff --git a/content/renderer/media/media_stream_audio_processor.cc b/content/renderer/media/media_stream_audio_processor.cc
index 272a70fe2f7dc8071d7bb5707da78a2a1fc4663b..efc9a5ee7591606ffb4e9c883ec6ca5a71d84288 100644
--- a/content/renderer/media/media_stream_audio_processor.cc
+++ b/content/renderer/media/media_stream_audio_processor.cc
@@ -409,6 +409,9 @@ void MediaStreamAudioProcessor::Stop() {
     playout_data_source_->RemovePlayoutSink(this);
     playout_data_source_ = NULL;
   }
+
+  if (echo_information_)
+    echo_information_->ReportAndResetAecDivergentFilterStats();
 }
 
 const media::AudioParameters& MediaStreamAudioProcessor::InputFormat() const {
@@ -757,7 +760,8 @@ int MediaStreamAudioProcessor::ProcessData(const float* const* process_ptrs,
   }
 
   if (echo_information_) {
-    echo_information_.get()->UpdateAecDelayStats(ap->echo_cancellation());
+    echo_information_->UpdateAecDelayStats(ap->echo_cancellation());
+    echo_information_->UpdateAecDivergentFilterStats(ap->echo_cancellation());
   }
 
   // Return 0 if the volume hasn't been changed, and otherwise the new volume.