Function resolve_hir_path_qualifier 

fn resolve_hir_path_qualifier(
    db: &dyn HirDatabase,
    resolver: &Resolver<'_>,
    path: &Path,
    store: &ExpressionStore,
) -> Option<PathResolution>

Resolves a path where we know it is a qualifier of another path.

For example, if we have:

mod my {
    pub mod foo {
        struct Bar;
    }

    pub fn foo() {}
}

then we know that foo in my::foo::Bar refers to the module, not the function.