Making hbos and hta OWNERS of webrtc/api/rtcstats*.

hbos and hta are webrtc/stats/ OWNERS. Public api headers relating to
rtcstats are placed in webrtc/api/ and implementations are placed in
webrtc/stats/. This ownership allows the rtcstats owners to own both .cc
and .h files.

For example, rtcstats.[h/cc] and rtcstatsreport.[h/cc].
(Soon there will also be rtcstats_objects.[h/cc] and more.)

BUG=chromium:627816

Review-Url: https://codereview.webrtc.org/2294693002
Cr-Commit-Position: refs/heads/master@{#13981}
diff --git a/webrtc/api/OWNERS b/webrtc/api/OWNERS
index 2160ffe..225b97a 100644
--- a/webrtc/api/OWNERS
+++ b/webrtc/api/OWNERS
@@ -8,6 +8,8 @@
 
 per-file androidvideotracksource.*=sakal@webrtc.org
 per-file androidvideotracksource.*=magjed@webrtc.org
+per-file rtcstats*=hbos@webrtc.org
+per-file rtcstats*=hta@webrtc.org
 
 # These are for the common case of adding or renaming files. If you're doing
 # structural changes, please get a review from a reviewer in this file.