6809233: Modal dialog blocks calling thread after it is hidden and disposed

Summary: Send WakingRunnable to toolkit to prevent early cleanup.
Reviewed-by: art, son

src/share/classes/java/awt/Dialog.java

@@ -1226,7 +1226,7 @@ public class Dialog extends Window {
         synchronized (getTreeLock()) {
             if (keepBlockingEDT) {
                 keepBlockingEDT = false;
-                PeerEvent wakingEvent = new PeerEvent(this, new WakingRunnable(), PeerEvent.PRIORITY_EVENT);
+                PeerEvent wakingEvent = new PeerEvent(getToolkit(), new WakingRunnable(), PeerEvent.PRIORITY_EVENT);
                 AppContext curAppContext = AppContext.getAppContext();
                 if (showAppContext != curAppContext) {
                     // Wake up event dispatch thread on which the dialog was