MIPS: Fix r24286 "ExtendStorageStub added, it is aimed for extending objects backing store when it runs out of space".

BUG=
R=ishell@chromium.org

Review URL: https://codereview.chromium.org/605873005

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24293 ce2b1a6d-e550-0410-aec6-3dcde31c8c00