Bug 1025669 - part 0, Add BaseMargin::ApplySkipSides, remove nsIFrame::Apply*SkipSides, and change call sites to use the former.  r=roc a=lmandel
Bug 1025669 - part 0.5, Add LogicalMargin::ApplySkipSides.  r=jfkthame a=lmandel
Bug 1025669 - part 1, Implement layout of block margins for box-decoration-break:clone.  r=roc a=lmandel
Bug 1025669 - part 2, some minor cleanup.  r=roc a=lmandel
Bug 1025669 - part 3, Tests for box-decoration-break:clone on block margins. a=lmandel
Bug 1031726 - Implement clip:rect() correctly when fragments are involved, for both box-decoration-break:slice/clone.  r=roc a=lmandel
Bug 1006326 - Enable the 'box-decoration-break' CSS property by default.  r=roc a=lmandel