Backed out 4 changesets (bug 861920, bug 861894) for mochitest failures.

Backed out changeset 69fcebb24095 (bug 861920)
Backed out changeset c39ceb11cb76 (bug 861920)
Backed out changeset d0aa77e7825b (bug 861894)
Backed out changeset 81e072111e98 (bug 861894)