Allow compareStub on ARM to take register in reverse order optionally.

BUG=none
TEST=none

Review URL: http://codereview.chromium.org/2850046/show

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5059 ce2b1a6d-e550-0410-aec6-3dcde31c8c00