Fix another missing #include build error from r251504.

TBR=vandebo@chromium.org

Review URL: https://codereview.chromium.org/168303004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@251513 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 251513