Fixes a DCHECK failure while invoking permission link

BUG=175893
TEST=Click on permission link and no DCHECK in debug builds.

Review URL: https://chromiumcodereview.appspot.com/12220142

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@182837 0039d316-1c4b-4281-b951-d872f2087c98
1 file changed