title: Window Session Crash
body: <p>I have the following code that add a View on top of a activity and remove it after 10 seconds.</p>
  
  <pre><code>public class MyActivity extends MainActivity {
      @Override
      protected void onCreate(Bundle arg0) {
          super.onCreate(arg0);
  
          final ImageView view = new ImageView(this);
          view.setBackgroundColor(Color.WHITE);
  
          getWindowManager()
                  .addView(
                          view,
                          new WindowManager.LayoutParams(LayoutParams.MATCH_PARENT,
                                  LayoutParams.MATCH_PARENT));
  
          new Handler().postDelayed(new Runnable() {
              @Override
              public void run() {
                  view.setVisibility(View.GONE);
                  getWindowManager().removeView(view);
              }
          }, 10000);
  
      }
  }
  </code></pre>
  
  <p>But two things happens here:
  First, the ImageView is not on top of all, I even didn't seen it on the Display.
  Second, after 10 seconds the following error happens and the application crash</p>
  
  <pre><code> Window Session Crash
   java.lang.NullPointerException
       at com.android.server.wm.WindowManagerService.relayoutWindow(WindowManagerService.java:2784)
       at com.android.server.wm.Session.relayout(Session.java:157)
       at android.view.IWindowSession$Stub.onTransact(IWindowSession.java:154)
       at com.android.server.wm.Session.onTransact(Session.java:111)
       at android.os.Binder.execTransact(Binder.java:320)
       at dalvik.system.NativeStart.run(Native Method)
      FATAL EXCEPTION: main
      java.lang.NullPointerException
          at android.os.Parcel.readException(Parcel.java:1327)
          at android.os.Parcel.readException(Parcel.java:1275)
          at android.view.IWindowSession$Stub$Proxy.relayout(IWindowSession.java:616)
          at android.view.ViewRoot.relayoutWindow(ViewRoot.java:3104)
          at android.view.ViewRoot.performTraversals(ViewRoot.java:1030)
          at android.view.ViewRoot.handleMessage(ViewRoot.java:2020)
          at android.os.Handler.dispatchMessage(Handler.java:99)
          at android.os.Looper.loop(Looper.java:132)
          at android.app.ActivityThread.main(ActivityThread.java:4028)
          at java.lang.reflect.Method.invokeNative(Native Method)
          at java.lang.reflect.Method.invoke(Method.java:491)
          at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:844)
          at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:602)
          at dalvik.system.NativeStart.main(Native Method)
  </code></pre>