Backed out changeset 21df28ade757 (bug 939608) PGO build issue
Backed out changeset 161bfee3f57a (bug 939608) PGO build issue
Bug 940153 - Build dom/encoding in unified mode; r=bzbarsky

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extra : rebase_source : ee7223645f90a009eafbced43b8cfc2b93aeb47c