Fix non-aura build break in r229103.

The change in r229103 missed adding a required header file.

R=sky@chromium.org

Review URL: https://codereview.chromium.org/28733006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@229444 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 229444