Add temporary hooks for the widgets feature team to wp_widget_control().

props westonruter.
see #26661.
Built from https://develop.svn.wordpress.org/trunk@26865


git-svn-id: http://core.svn.wordpress.org/trunk@26751 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Add comments for temporary hooks. see #26661.
Built from https://develop.svn.wordpress.org/trunk@26866


git-svn-id: http://core.svn.wordpress.org/trunk@26752 1a063a9b-81f0-0310-95a4-ce76da25c4cd