Clear reference to Global Actions Dialog after it is dismissed

Fixes: 141681179
Test: manual, atest
Change-Id: Ic8bdc77a3b590577d565f2225352be192ea8fabf

packages/SystemUI/src/com/android/systemui/globalactions/GlobalActionsDialog.java

@@ -419,9 +419,7 @@ public class GlobalActionsDialog implements DialogInterface.OnDismissListener,
                                 new GlobalActionsPanelPlugin.Callbacks() {
                                     @Override
                                     public void dismissGlobalActionsMenu() {
-                                        if (mDialog != null) {
-                                            mDialog.dismiss();
-                                        }
+                                        dismissDialog();
                                     }
 
                                     @Override
@@ -916,6 +914,9 @@ public class GlobalActionsDialog implements DialogInterface.OnDismissListener,
 
     /** {@inheritDoc} */
     public void onDismiss(DialogInterface dialog) {
+        if (mDialog == dialog) {
+            mDialog = null;
+        }
         mWindowManagerFuncs.onGlobalActionsHidden();
         if (mShowSilentToggle) {
             try {