That makes it easier to maintain the code---one should care less
about releasing the memory as smart pointers would take care of
this.

Switch to ScopedVector instead Vector for the same semantics in
src/builtins.cc

Review URL: http://codereview.chromium.org/1737023

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4593 ce2b1a6d-e550-0410-aec6-3dcde31c8c00