Re-apply http://codereview.chromium.org/175045 with the single change that the line

  mov(scratch, Operand(new_space_allocation_top));

have been added to MacroAssembler::UndoAllocationInNewSpace after the #endif. Without this change the top was not reset.

TBR=erik.corry@gmail.com
Review URL: http://codereview.chromium.org/184009

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2815 ce2b1a6d-e550-0410-aec6-3dcde31c8c00