The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/89d302f64f2bfc4967ec88e0eecd6c4cebcd45d2

commit 89d302f64f2bfc4967ec88e0eecd6c4cebcd45d2
Author: grunell <grunell@chromium.org>
Date: Wed Jun 29 14:23:13 2016

Add UMA stats for AEC filter divergence metric.

Stats are reported when MediaStreamAudioProcessor::Stop() is called. This is typically when a WebRTC call is ended.

BUG= 623607 

Review-Url: https://codereview.chromium.org/2103483002
Cr-Commit-Position: refs/heads/master@{#402801}

[modify] https://crrev.com/89d302f64f2bfc4967ec88e0eecd6c4cebcd45d2/content/renderer/media/media_stream_audio_processor.cc
[modify] https://crrev.com/89d302f64f2bfc4967ec88e0eecd6c4cebcd45d2/content/renderer/media/media_stream_audio_processor.h
[modify] https://crrev.com/89d302f64f2bfc4967ec88e0eecd6c4cebcd45d2/content/renderer/media/media_stream_audio_processor_options.cc
[modify] https://crrev.com/89d302f64f2bfc4967ec88e0eecd6c4cebcd45d2/content/renderer/media/media_stream_audio_processor_options.h
[modify] https://crrev.com/89d302f64f2bfc4967ec88e0eecd6c4cebcd45d2/content/renderer/media/media_stream_audio_processor_unittest.cc
[modify] https://crrev.com/89d302f64f2bfc4967ec88e0eecd6c4cebcd45d2/tools/metrics/histograms/histograms.xml