Act on outbound ground metamessages before checking for inertness.

os.rkt

@@ -292,16 +292,16 @@
 ;; Runs its argument VM until it becomes (provably) inert.
 (define (ground-vm pattern-predicate boot)
   (let loop ((transition (run-vm (make-vm pattern-predicate boot))))
+    (for-each (lambda (thunk) (thunk)) (kernel-mode-transition-messages transition))
     (when (not (nested-vm-inert? (kernel-mode-transition-subscription transition)))
       (match transition
 	[(kernel-mode-transition (subscription new-state
 					       polling-k
 					       message-handlers
 					       '())
-				 outbound-messages
+				 _
 				 '()
 				 '())
-	 (for-each (lambda (thunk) (thunk)) outbound-messages)
 	 (define inbound-messages
 	   (map (match-lambda [(message-handler e k) (wrap-evt e (lambda (v) (cons v k)))])
 		message-handlers))