MIPS: Additional work to get array literal allocation tracking working, even with --always-opt

Port r13406 (796a9f11)

BUG=
TEST=

Review URL: https://codereview.chromium.org/12026002
Patch from Akos Palfi <palfia@homejinni.com>.

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@13441 ce2b1a6d-e550-0410-aec6-3dcde31c8c00