Use no barrier size accessor in FreeListCategory::SumFreeList.

BUG=
R=jarin@chromium.org

Review URL: https://codereview.chromium.org/230613002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@20610 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Remove calls to non-handlified version of GetProperty(name).

R=ishell@chromium.org

Review URL: https://codereview.chromium.org/229973004

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@20611 ce2b1a6d-e550-0410-aec6-3dcde31c8c00