7145980: Dispose method of window.java takes long

Reviewed-by: anthony

src/share/classes/java/awt/Component.java

@@ -10070,11 +10070,12 @@ public abstract class Component implements ImageObserver, MenuContainer,
         }
         Window window = getContainingWindow();
         if (window != null) {
-            if (!window.hasHeavyweightDescendants() || !window.hasLightweightDescendants()) {
+            if (!window.hasHeavyweightDescendants() || !window.hasLightweightDescendants() || window.isDisposing()) {
                 if (mixingLog.isLoggable(PlatformLogger.FINE)) {
                     mixingLog.fine("containing window = " + window +
                             "; has h/w descendants = " + window.hasHeavyweightDescendants() +
-                            "; has l/w descendants = " + window.hasLightweightDescendants());
+                            "; has l/w descendants = " + window.hasLightweightDescendants() +
+                            "; disposing = " + window.isDisposing());
                 }
                 return false;
             }

src/share/classes/java/awt/Window.java

@@ -226,6 +226,7 @@ public class Window extends Container implements Accessible {
     static boolean systemSyncLWRequests = false;
     boolean     syncLWRequests = false;
     transient boolean beforeFirstShow = true;
+    private transient boolean disposing = false;
 
     static final int OPENED = 0x01;
 
@@ -1162,6 +1163,8 @@ public class Window extends Container implements Accessible {
     void doDispose() {
     class DisposeAction implements Runnable {
         public void run() {
+            disposing = true;
+            try {
                 // Check if this window is the fullscreen window for the
                 // device. Exit the fullscreen mode prior to disposing
                 // of the window if that's the case.
@@ -1192,6 +1195,9 @@ public class Window extends Container implements Accessible {
                     }
                 }
                 clearCurrentFocusCycleRootOnHide();
+            } finally {
+                disposing = false;
+            }
         }
     }
         DisposeAction action = new DisposeAction();
@@ -2734,6 +2740,10 @@ public class Window extends Container implements Accessible {
         return visible;
     }
 
+    boolean isDisposing() {
+        return disposing;
+    }
+
     /**
      * @deprecated As of J2SE 1.4, replaced by
      * {@link Component#applyComponentOrientation Component.applyComponentOrientation}.