MIPS: Encode CEntryStub properties in the minor key.

Port r23355 (1be1443)

Original commit message:
Eventually, all stubs should encode its properties in the minor key
so that stubs can be restored directly from the stub key.

BUG=
R=paul.lind@imgtec.com

Review URL: https://codereview.chromium.org/505823003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@23371 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Merge remote-tracking branch 'upstream/bleeding_edge' into bleeding_edge