R=ricow@chromium.org

BUG=none
TEST=cctest/test-lockers/LockerUnlocker,cctest/test-lockers/LockTwiceAndUnlock,cctest/test-lockers/SeparateIsolatesLocksNonexclusive

Review URL: http://codereview.chromium.org//7334007

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8597 ce2b1a6d-e550-0410-aec6-3dcde31c8c00