MIPS: Merge KeyedLoad and NamedLoad stub compiler code.
MIPS: Merge KeyedLoad and NamedLoad stub compiler code.

Port r13579 (e640269)

BUG=

Review URL: https://chromiumcodereview.appspot.com/12186003
Patch from Paul Lind <plind44@gmail.com>.

git-svn-id: b158db1e4b4ab85d4c9e510fdef4b1e8c614b15b@13580 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

UniversalFuture/moosh,UniversalFuture/moosh,UniversalFuture/moosh,UniversalFuture/moosh