Revert "Request csrf tokens in JS when supported"

Depends on core change which was reverted: I429b609b626af3
Proofreading is currently broken, as reported in translatewiki.net and
mediawiki.org.

This reverts commit 1653a55dd5541c0d627cc2b92b70acdae56d9c83.

(cherry picked from commit 846b899d5754a621a95a24b696017f110a777957)

Change-Id: Ie1d788b9a92b29b657c2cc526ab5ccf9d519e5af