Fix for iOS build after r231478.

This adds dependencies on ui_unittests target to make iOS happy again.

BUG=299841
TEST=None
R=lliabraa@chromium.org, ben@chromium.org

Review URL: https://codereview.chromium.org/54583002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@232841 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 232841