We weren't always setting DECL_CONTEXT for parm decls.  Which caused me 
some issues in the modules branch.  Fixed by making the callers of the 
parm-decl builders pass in the function decl.  I suspect the places in 
grokdecl dealing with declaring via typedef (where I pass NULL) will 
need addressing later on, but this seems a useful cleanup.

Applied to trunk.

nathan
-- 
Nathan Sidwell