Function find_local_import_locations 

fn find_local_import_locations<'db>(
    ctx: &'db FindPathCtx<'db>,
    item: ItemInNs,
    visited_modules: &mut FxHashSet<(ItemInNs, ModuleIdLt<'db>)>,
    cb: impl FnMut(&mut FxHashSet<(ItemInNs, ModuleIdLt<'db>)>, &Name, ModuleIdLt<'db>),
)

Finds locations in from.krate from which item can be imported by from.