GitLab

Make sure the onLocalDescriptionError callback is set before it can possibly
be called as a side-effect of webkitGetUserMedia().

BUG=339286
TEST=local build, run on desktop Linux

Review URL: https://codereview.chromium.org/149703004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@247953 0039d316-1c4b-4281-b951-d872f2087c98