'SpecialContributions::getForm::filters': Called with a list of filters to render
on Special:Contributions.
$sp: SpecialContributions object, for context
-&$filters: List of filters rendered as HTML
+&$filters: List of filter object definitions (compatible with OOUI form)
'SpecialListusersDefaultQuery': Called right before the end of
UsersPager::getDefaultQuery().