Unbind from dream overlay in onUnbind.

If a dream is unbound before finish, unbinding from the overlay service
will not occur before onDestroy. This will result in an exception from
unbinding from a non registered service. This change ensures the dream
service unbinds from the overlay service when unbound.

Test: atest DreamManagerServiceTests#testForceStopStubbornDream
Fixed: 229824204
Change-Id: Id708b9119c5498bf9632b21a539c3ca7f5506737

core/java/android/service/dreams/DreamService.java

@@ -999,6 +999,14 @@ public class DreamService extends Service implements Window.Callback {
         return mDreamServiceWrapper;
     }
 
+    @Override
+    public boolean onUnbind(Intent intent) {
+        // We must unbind from any overlay connection if we are unbound before finishing.
+        mOverlayConnection.unbind(this);
+
+        return super.onUnbind(intent);
+    }
+
     /**
      * Stops the dream and detaches from the window.
      * <p>