Back out changeset 1e1f3cd07479 (Bug 898308) as part of handling regressions in Bug 900910; r=gavin, r=dao, a=akeybl, ba=gavin

X-Git-Commit-ID: a7ea8b4aa49954a3c0cb7c53da144216ff1f6775
This reverts git commit 3ab3481e58403d4d33138dc4623d222fe840259d.
Bug 910881 - Do not call RasterImage::DoError off the main thread. r=jdm, a=abillings
Bug 869406 - Really enforce non-parallel build of ICU. r=gps, a=akeybl
Bug 898926 - xbl:children elements are insertion points if they're inactive. r=sicking, a=abillings
Bug 898926 - Add reftest. r=sicking, a=abillings
Bug 912534. r=nbp, a=akeybl