MakeCode functions in the CompilationInfo structure.  This makes it
easier to add new arguments and makes all arguments uniformly
available to the various backends.
Review URL: http://codereview.chromium.org/566008

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3789 ce2b1a6d-e550-0410-aec6-3dcde31c8c00