Revert "Further ElementsAccessor handlification (GetKeyForIndex(), GetCapacity(), GetType() and GetAttributes())."

This reverts commit r20606 for breaking tests on windows.

TBR=dcarney@chromium.org

Review URL: https://codereview.chromium.org/230603002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@20607 ce2b1a6d-e550-0410-aec6-3dcde31c8c00