When undeleting past revisions on a page that exists, the history list
isn't visibly updated to users; the pre-undelete version cached by the
browser continues to be shown. It needs to update the page_touched
timestamp to make sure history page caches are cleared.

If the one of the undeleted revisions is newer than the current revision,
it also needs to update page_latest and send squid cache clearances.

Version: unspecified
Severity: normal