method ensures that there are no allocations during the setup.

This fixes test breakage on Linux in debug mode where allocation
happened while the debug info object was not fully set up making
verify heap unhappy.


git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@70 ce2b1a6d-e550-0410-aec6-3dcde31c8c00