why must a NamespaceAliasDeclaration's importIdentifier not be explicitlyGlobal?

[David Nolden]

I think, this is only for consistency. A namespace alias declaration
is always global, and the "explicitly global" flag is simply not
required. That flag is actually just a flag for lookup. For example,
when you call "declaration->qualifiedIdentifier()", then the result
also does not have this flag set, even though it is global of course.

The flag could be removed in setImportIdentifier. However, when you
sometimes set an import identifier _with_ the flag and sometimes
_without_, then you'll be probably doing something wrong, after all
the "explicitly global" should have some special meaning in your
language.

Greetings, David