X87:  Minor-key-ify remaining code stubs

port r23643.

original commit message:

  Minor-key-ify remaining code stubs

BUG=
R=weiliang.lin@intel.com

Review URL: https://codereview.chromium.org/542043002

Patch from Jing Bao <jing.bao@intel.com>.

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@23711 ce2b1a6d-e550-0410-aec6-3dcde31c8c00