Fix delivery error-checking missed in r6151.
Fix delivery error-checking missed in r6151.

Gets rid of quite a bit of false-warning logging in WebRtcVideoEngine2.

BUG=3228
R=perkj@webrtc.org
TBR=pthatcher@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/16529004

Cr-Mirrored-From: https://chromium.googlesource.com/external/webrtc
Cr-Mirrored-Commit: 1e019d10b8bcd96e8cf6b3d3df2730449fbed939

sippet/talk,sippet/talk,sippet/talk,sippet/talk,sippet/talk