Use common allocation choke point in Heap::AllocateConstantPoolArray.

R=hpayer@chromium.org

Review URL: https://codereview.chromium.org/37003003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@17341 ce2b1a6d-e550-0410-aec6-3dcde31c8c00