Add pbos@webrtc.org to webrtc/video_engine/OWNERS.

BUG=
R=stefan@webrtc.org

Review URL: https://codereview.webrtc.org/1244733003

Cr-Commit-Position: refs/heads/master@{#9640}
diff --git a/webrtc/video_engine/OWNERS b/webrtc/video_engine/OWNERS
index 5e47b1a..a8201f0 100644
--- a/webrtc/video_engine/OWNERS
+++ b/webrtc/video_engine/OWNERS
@@ -1,4 +1,5 @@
 mflodman@webrtc.org
+pbos@webrtc.org
 stefan@webrtc.org
 
 per-file *.isolate=kjellander@webrtc.org