Question: CREATE EXTENSION and create schema permission?

CreateExtension() possibly creates a new schema when the supplied
extension was not relocatable and the target schema was given by
control file of the extension.
However, it allows users to create a new schema with his ownership,
even if current user does not have permission to create a new schema.
   Oid         extowner = GetUserId();     :   else if (control->schema != NULL)   {       /*        * The extension is
notrelocatable and the author gave us a schema        * for it.  We create the schema here if it does not already
exist.       */       schemaName = control->schema;       schemaOid = get_namespace_oid(schemaName, true);
 
       if (schemaOid == InvalidOid)       {           schemaOid = NamespaceCreate(schemaName, extowner);           /*
Advancecmd counter to make the namespace visible */           CommandCounterIncrement();       }   }
 

It seems to me that we should inject permission checks here like as
CreateSchemaCommand() doing.
   /*    * To create a schema, must have schema-create privilege on the current    * database and must be able to
becomethe target role (this does not    * imply that the target role itself must have create-schema privilege).    *
Thelatter provision guards against "giveaway" attacks.  Note that a    * superuser will always have both of these
privilegesa fortiori.    */   aclresult = pg_database_aclcheck(MyDatabaseId, saved_uid, ACL_CREATE);   if (aclresult !=
ACLCHECK_OK)      aclcheck_error(aclresult, ACL_KIND_DATABASE,                      get_database_name(MyDatabaseId));
 

I didn't follow the discussion about extension so much when it got merged.
Please tell me, if it was a topic already discussed before.

Thanks,
-- 
KaiGai Kohei <kaigai@kaigai.gr.jp>