-inl.h files should only contains small inline functions and
no class declarations. Implementation moved to codegen.cc since
it's not a performance critical class (only used in DEBUG mode).
 
Review URL: http://codereview.chromium.org/585004

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3812 ce2b1a6d-e550-0410-aec6-3dcde31c8c00