Fix DU.makeWrapperForNode to handle misnested A-tags

* One more area where we need to deal with badly nested A-tags.
  What a fricking annoyance! We should simply run a bot and fix
  all these uses and not support this broken wikitext.

* Fixes 20 selser failures that were mostly introduced in the
  patch (commit ca9e7600) that introduced scoped parsing and
  enabled it for A-tags.

Change-Id: Ic58d175b45b14d20d126539c49822ff2d473ec19