Turn some usages of NewArray with DeleteArray in the same scope into ScopedVector...

Turn some usages of NewArray with DeleteArray in the same scope into ScopedVector or SmartPointer.

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