Auto merge of rust-lang#34871 - petrochenkov:inherent, r=jseyfried

Do not resolve inherent static methods from other crates prematurely

Under some specific circumstances paths like `Type::method` can be resolved early in rustc_resolve instead of type checker. `Type` must be defined in another crate, it should be an enum or a trait object (i.e. a type that acts as a "module" in resolve), and `method` should be an inherent static method.
As a result, such paths don't go through `resolve_ufcs`, may be resolved incorrectly and break some invariants in type checker. This patch removes special treatment of such methods.

The removed code was introduced in rust-lang@2bd46e7 to fix a problem that no longer exists.

r? @jseyfried

src/librustc_metadata/decoder.rs

@@ -687,32 +687,6 @@ fn each_child_of_item_or_crate<F, G>(cdata: Cmd,
         }
     }
 
-    // As a special case, iterate over all static methods of
-    // associated implementations too. This is a bit of a botch.
-    // --pcwalton
-    for inherent_impl_def_id_doc in reader::tagged_docs(item_doc,
-                                                             tag_items_data_item_inherent_impl) {
-        let inherent_impl_def_id = item_def_id(inherent_impl_def_id_doc, cdata);
-        if let Some(inherent_impl_doc) = cdata.get_item(inherent_impl_def_id.index) {
-            for impl_item_def_id_doc in reader::tagged_docs(inherent_impl_doc,
-                                                                 tag_item_impl_item) {
-                let impl_item_def_id = item_def_id(impl_item_def_id_doc,
-                                                   cdata);
-                if let Some(impl_method_doc) = cdata.get_item(impl_item_def_id.index) {
-                    if let StaticMethod = item_family(impl_method_doc) {
-                        // Hand off the static method to the callback.
-                        let static_method_name = item_name(impl_method_doc);
-                        let static_method_def_like = item_to_def_like(cdata, impl_method_doc,
-                                                                      impl_item_def_id);
-                        callback(static_method_def_like,
-                                 static_method_name,
-                                 item_visibility(impl_method_doc));
-                    }
-                }
-            }
-        }
-    }
-
     for reexport_doc in reexports(item_doc) {
         let def_id_doc = reader::get_doc(reexport_doc,
                                          tag_items_data_item_reexport_def_id);

src/test/compile-fail/use-from-trait-xc.rs

@@ -31,6 +31,6 @@ use use_from_trait_xc::Bar::new as bnew;
 //~^ ERROR unresolved import `use_from_trait_xc::Bar::new`
 
 use use_from_trait_xc::Baz::new as baznew;
-//~^ ERROR `baznew` is not directly importable
+//~^ ERROR unresolved import `use_from_trait_xc::Baz::new`
 
 fn main() {}