Cleaning up tooltip for ToggleFeaturePreferenceFragment

Cleaning up QS tile tooltip in the Settings page in onDestroy to avoid
leaking the window.

Bug: 279547549
Test: manually check only one tooltip exists
Change-Id: I781cdba1be7be0315de12cd57620521b40969aee

src/com/android/settings/accessibility/ToggleFeaturePreferenceFragment.java

@@ -296,6 +296,10 @@ public abstract class ToggleFeaturePreferenceFragment extends DashboardFragment
     public void onDestroyView() {
         super.onDestroyView();
         removeActionBarToggleSwitch();
+        final boolean isTooltipWindowShowing = mTooltipWindow != null && mTooltipWindow.isShowing();
+        if (isTooltipWindowShowing) {
+            mTooltipWindow.dismiss();
+        }
     }
 
     @Override