avm2: `toString` of stage objects should work the same way as other objects

core/src/avm2/object/stage_object.rs

@@ -310,10 +310,6 @@ impl<'gc> TObject<'gc> for StageObject<'gc> {
         .into())
     }
 
-    fn to_string(&self, _mc: MutationContext<'gc, '_>) -> Result<Value<'gc>, Error> {
-        Ok("todo: movieclip values".into())
-    }
-
     fn value_of(&self, _mc: MutationContext<'gc, '_>) -> Result<Value<'gc>, Error> {
         Ok(Value::Object(Object::from(*self)))
     }