Abstractly a lexscope is just a mapping from names to vl-lexscope-entry objects, i.e. a vl-lexscope-decls object. The
decls field has this mapping, for names that are explicitly declared or
imported explicitly from packages at the current scope. But for wildcard
imports, we don't store imported symbols in the decls map. Instead, we keep an
additional field wildpkgs mapping each wildcard-imported package name to
the scopeitem-alist of the declarations of that package. Whenever we look up a
name in a lexscope, we also look up the name in all of these package
scopeitem-alists to collect the list of packages that the name is imported
from (populating the wildpkgs field of the vl-lexscope-entry'
object.
