Bug 815666 - Add a helper class to coalesce frames that need their overflow updated. r=roc a=akeybl
Bug 815666 - Use OverflowUpdateTracker to avoid calling UpdateOverflow on the same frame multiple times. r=roc a=akeybl
Bug 822906 - Add SplayTree to mfbt. r=waldo a=akeybl
Bug 822906 - Use SplayTree to remove deleted frames from RestyleTracker. r=roc a=akeybl
Back out 7f84bf06751d:a3a21c01dab8 (bug 822906) and 6e334c229091:97e0102c59c0 (bug 815666) for bustage
a=backout
Bug 827070.  r=smontagu a=bbajaj
bug 796475 - proxy auth cancelation rendering fix r=jduell a=akeybl