message: Add kron as owner of api/uma_metrics.h
  kron is an owner of UMA metrics for WebRTC in chromium,
  see tools/metrics/histograms/histograms_xml/web_rtc/OWNERS
  Cr-Commit-Position: refs/heads/master@{#34268}
diff: @@ -11,15 +11,4 @@ per-file peer_connection*=hbos@webrtc.org
  per-file DEPS=mbonadei@webrtc.org
  -# Please keep this list in sync with Chromium's //base/metrics/OWNERS and
  -# send a CL when you notice any difference.
  -# Even if people in the list below cannot formally grant +1 on WebRTC, it
  -# is good to get their LGTM before sending the CL to one of the folder OWNERS.
  -per-file uma_metrics.h=asvitkine@chromium.org
  -per-file uma_metrics.h=bcwhite@chromium.org
  -per-file uma_metrics.h=caitlinfischer@google.com
  -per-file uma_metrics.h=holte@chromium.org
  -per-file uma_metrics.h=isherman@chromium.org
  -per-file uma_metrics.h=jwd@chromium.org
  -per-file uma_metrics.h=mpearson@chromium.org
  -per-file uma_metrics.h=rkaplow@chromium.org
  +per-file uma_metrics.h=kron@webrtc.org
  