Bug 956967. If we have to fallback to our default Azure backend, we must support that backend. r=nical

--HG--
extra : rebase_source : 2cc8d34078df6db64353cf5236572f085c2be72e
Bug 956967. Don't use direct2d if we forcing d3d9. r=Bas

--HG--
extra : rebase_source : 5a4505f9fe043cce965b11a0d1c33815d2b0be3e
Bug 943249 - Make <[i]frame scrolling> compatible with IE/Chrome; that is scrolling="no" (and synonyms) suppress scrollbars (as before), anything else has no effect.  r=bz
Bug 943249 - Reftests.
Bug 943249 - Repair a few reftests that depend on the old @scrolling behavior.
Bug 958249 - The first ::first-letter continuation should display all sides of the border, the following continuations none.  r=dholbert