Avoid allocations in Object.observe access check tests

BUG=v8:2907
R=mstarzinger@chromium.org

Review URL: https://codereview.chromium.org/24999007

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@17090 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Inline some more compare operations.

BUG=
R=hpayer@chromium.org

Review URL: https://codereview.chromium.org/25009003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@17091 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
MIPS: Fix test262 failures and x64 compile failure.

Port r17082 (fc909df)

BUG=
R=plind44@gmail.com

Review URL: https://codereview.chromium.org/25560006

Patch from Balazs Kilvady <kilvadyb@homejinni.com>.

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@17092 ce2b1a6d-e550-0410-aec6-3dcde31c8c00