Fix object identities for pg_conversion objects

We were neglecting to schema-qualify them.

Backpatch to 9.3, where object identities were introduced as a concept
by commit f8348ea.

Author: alvherre

src/backend/catalog/objectaddress.c

@@ -2785,15 +2785,19 @@ getObjectIdentity(const ObjectAddress *object)
 			{
 				HeapTuple	conTup;
 				Form_pg_conversion conForm;
+				char	   *schema;
 
 				conTup = SearchSysCache1(CONVOID,
 										 ObjectIdGetDatum(object->objectId));
 				if (!HeapTupleIsValid(conTup))
 					elog(ERROR, "cache lookup failed for conversion %u",
 						 object->objectId);
 				conForm = (Form_pg_conversion) GETSTRUCT(conTup);
-				appendStringInfo(&buffer, "%s",
-								 quote_identifier(NameStr(conForm->conname)));
+				schema = get_namespace_name(conForm->connamespace);
+				appendStringInfoString(&buffer,
+								quote_qualified_identifier(schema,
+														   NameStr(conForm->conname)));
+				pfree(schema);
 				ReleaseSysCache(conTup);
 				break;
 			}