Explicitly set expected number of properties for instances of builtin types.

Explicitly set expected number of properties for instances of builtin types.

We used to inherit an estimate on the expected number of properties in
%SetCode. It is not accurate and does not help for the types where
adding custom properties is rare (String, Date, etc.).

Review URL: http://codereview.chromium.org/3191026

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5348 ce2b1a6d-e550-0410-aec6-3dcde31c8c00