Fix logic error in assert in IsUndeclaredGlobal()

Recent changes in IC logic meant that CallStubs no longer use the Contextual bit. IsUndeclaredGlobal() needed to adjust for that.

In fact, now the CL has morphed to remove the notion of storing contextual state in the IC at all, it just becomes some extra ic state of the load ic. This took some adjustment in harmony code to use the global receiver for certain stores.

Now it's clearer that only LoadICs actually record any information about contextual or not.

R=verwaest@chromium.org

Review URL: https://codereview.chromium.org/140943002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@18660 ce2b1a6d-e550-0410-aec6-3dcde31c8c00