Auto merge of #112426 - Bryanskiy:full_priv_ev, r=petrochenkov

increase the accuracy of effective visibilities calculation

Effective visibilities are calculated lazily due to performance restrictions.  Therefore

- crate should be walked at least 1 time in `compute_effective_visibilities` pass
- Impl's should always be in the effective visibilities table

to ensure that the table is filled in correctly.

r? `@petrochenkov`

compiler/rustc_resolve/src/effective_visibilities.rs

@@ -81,7 +81,7 @@ impl<'r, 'a, 'tcx> EffectiveVisibilitiesVisitor<'r, 'a, 'tcx> {
             def_effective_visibilities: Default::default(),
             import_effective_visibilities: Default::default(),
             current_private_vis: Visibility::Restricted(CRATE_DEF_ID),
-            changed: false,
+            changed: true,
         };
 
         visitor.def_effective_visibilities.update_root();