Fix video_WebRtcPerf failure "Cannot find histogram".

webkitGetUserMedia requires 3 arguments. The test did not pass
the error callback parameter and failed. W3C Media Capture and
Streams document says the error callback cannot be null and is
not optional. Add the error callback to fix this.

BUG=chromium:362242
TEST=Run the test on CrOS.

Change-Id: Icbc028936d20396476dbb7399ac2a10f1d61967e
Previous-Reviewed-on: https://chromium-review.googlesource.com/194241
(cherry picked from commit 9833fc65c3ef3f94215f42b1ef925c8a2da75983)
Reviewed-on: https://chromium-review.googlesource.com/194885
Reviewed-by: Wu-Cheng Li <wuchengli@chromium.org>
Tested-by: Wu-Cheng Li <wuchengli@chromium.org>
1 file changed