Instead of adding code dependencies on stable during
graph creation, we now add them during code generation
for those HCheckMaps that survived dead code elimination.

R=svenpanne@chromium.org

Review URL: https://codereview.chromium.org/264973013

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@21139 ce2b1a6d-e550-0410-aec6-3dcde31c8c00