cc: Initialize integer field in IOSurfaceLayerImpl.

Otherwise when we initalize the renderer, we may try to delete a
resource that does not exist, or worse delete on that does.

R=piman@chromium.org, piman
BUG=

Review URL: https://codereview.chromium.org/24686002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@225531 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 225531