This changes the revert notification (special page version) to link
to the contributions page for anonymous (logged out) editors.
It still links to the user page for logged in editors.
Bug: T55564
Change-Id: Ib1f17fb88237b96cda63dd30ed488a8ffd84750e
The logic to get the URL for an icon was duplicated in the
EmailFormatter and BasicFormatter. It is now in the abstract
NotificationFormatter, which EmailFormatter and BasicFormatter now
use.
Changes in logic:
* Throw an exception if an invalid notification type is provided instead
of a PHP notice
* icons using 'url' may have different ltr/rtl icons
* Throw exception if icon is supposed to have different icons for
ltr/rtl, but doesn't, instead of debug logging
The new function is static so it can be used in EmailFormatter as it
does not inherit from NotificationFormatter.
Bug: T60726
Change-Id: Ia3c01c35f58eed8cc2c039249ab1ec1a80a8abbb