Fix a stale comment.

Fix stale comment left-over from crrev.com/11308356

BUG=

Review URL: https://codereview.chromium.org/115993005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@242592 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 242592