GitLab

Avoids a NULL deref when then image filter is NULL.

BUG=wkb.ug/103990
TBR=jamesr
NOTRY=true

Review URL: https://chromiumcodereview.appspot.com/11308354

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@171014 0039d316-1c4b-4281-b951-d872f2087c98