MIPS: port Handlify simple functions of [keyed] load stub compiler.

Port r9773 (4cf7a453)

BUG=
TEST=

Review URL: http://codereview.chromium.org/8390035

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9785 ce2b1a6d-e550-0410-aec6-3dcde31c8c00