Bug 886579 - Better errors for JS tests, r=mdas
Bug 888673 - Update Yarr yet again. r=sstangl

--HG--
extra : rebase_source : 129ba2817818f5c666b9d1bd4402a76999bff895
Bug 888613 - Micro-optimization of js::ToInteger. r=jwalden

--HG--
extra : rebase_source : 3e5774bec875860659b500ae9ab87c404f213c47