(Bug 50179) Unhandled wikitext escaping for quotes after i/b nodes

* Updated html2wt escaping tests for quotes (which now passes
  and would fail before this patch).

Change-Id: I1e47c651324f40d7ff562f0eeb6f19bd6989ffd2
Merge "(Bug 50179) Unhandled wikitext escaping for quotes after i/b nodes"