Bug 414087 (part 1) - Clean up the style of StackArena.{h,cpp}.  r=bz.
Bug 414087 (part 2) - Remove insignificant wasted space in StackBlock.  r=bz.
Bug 919958 - Odinmonkey: disable movement of heap loads as a workaround while the real problem is explored (r=bbouvier)

--HG--
extra : rebase_source : 7ec73d4d0093086e61d1a1f99ffa8afcd33017aa