Feed is_type_alias_impl_trait for RPITITs on the trait side

compiler/rustc_middle/src/query/mod.rs

@@ -191,6 +191,7 @@ rustc_queries! {
     {
         desc { "determine whether the opaque is a type-alias impl trait" }
         separate_provide_extern
+        feedable
     }
 
     query unsizing_params_for_adt(key: DefId) -> &'tcx rustc_index::bit_set::BitSet<u32>

compiler/rustc_ty_utils/src/assoc.rs

@@ -289,6 +289,8 @@ fn associated_item_for_impl_trait_in_trait(
         InternalSubsts::identity_for_item(tcx, opaque_ty_def_id.to_def_id()),
     )));
 
+    trait_assoc_ty.is_type_alias_impl_trait(false);
+
     // Copy generics_of of the opaque type item but the trait is the parent.
     trait_assoc_ty.generics_of({
         let opaque_ty_generics = tcx.generics_of(opaque_ty_def_id);