Bug 1057098 - Rename ElementRestyler::Restyle{Before,After}Pseudo to MaybeReframeFor{Before,After}Pseudo.  r=bzbarsky
Bug 1057129 patch 1 - Make AddStyleUpdatesTo handle pseudo-elements.  r=birtles

This (like patch 2) posts restyles directly to the pseudo-element
content nodes, which is a new thing.

This isn't needed right now since AddStyleUpdatesTo is currently only
used when updating main-thread-suppressed animations running on the
compositor.  However, it will be needed once we depend on
AddStyleUpdatesTo for bug 960465.  And it will have an effect now since
AddStyleUpdatesTo actually adds all animations rather than only the ones
that are suppressed from running on the main thread.
Bug 1057129 patch 2 - Post all animation restyles directly to pseudo-elements.  r=birtles

This (like patch 1) posts restyles directly to the pseudo-element
content nodes, which is a new thing as of this bug.  Previously we'd
have posted eRestyle_Subtree restyles to the pseudo element's real
element (i.e., the parent of the pseudo-element content node).

This changes the way we post animation restyles for ::before and ::after
pseudo-elements with animations on them.
Bug 1057129 patch 3 - Post restyles from CheckAnimationRule directly to pseudo-elements.  r=birtles

This matches patch 2, and also fixes an incorrect use of eRestyle_Self
on the parents of pseudo-elements in order to restyle those
pseudo-elements, where it would not previously have been effective.

This should all be temporary, since this code can go away with bug
960465, when animation phases are removed.