X87: Avoid one repeated property lookup when computing load ICs.

  r22802 touches X87 port but it is not changed completely.

port r22802.

original commit message:
  Avoid one repeated property lookup when computing load ICs.

BUG=
R=weiliang.lin@intel.com

Review URL: https://codereview.chromium.org/441873002

Patch from Chunyang Dai <chunyang.dai@intel.com>.

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@22839 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
X87: Cleanup in stub-cache.cc; remove unused ArrayLength store ICs.

port r22805

original commit message:

  Cleanup in stub-cache.cc; remove unused ArrayLength store ICs.

BUG=
R=weiliang.lin@intel.com

Review URL: https://codereview.chromium.org/438163003

Patch from Chunyang Dai <chunyang.dai@intel.com>.

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@22840 ce2b1a6d-e550-0410-aec6-3dcde31c8c00