Call WikiPage::doViewUpdates also on missing article page view

Reset notification timestamp also for deleted pages on the watchlist,
this will give a empty notification on api's
prop=info&inprop=notificationtimestamp for the timestamp after visiting
a deleted page.

This also reset the remaining newtalk flags for anon user talks which
are effected by bug 14077.

Change-Id: Ibdb22ab1e0bea02b6ef730cd5737f91801b8d700
Merge "Call WikiPage::doViewUpdates also on missing article page view"