title: Closing activity should kill app even from background
body: <p>I am creating only one activity of the app. And want that while closing the activity the app should also be removed from the background.</p>
  <pre><code>openIntent = new Intent(context, WebActivity.class);
              openIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
              context.startActivity(openIntent);
  </code></pre>
  <p>I have tied many ways but every time the app stays in the background.</p>
  <pre><code>Process.killProcess(Process.myPid());
  System.exit(0);
  finishAffinity();
  </code></pre>
  <p>I am using a background service. It is a video call activity like WhatsApp. So when the notification from firebase comes then I have to start calling activity. If the user presses the cancels call button then I have to kill the activity like on WhatsApp. But by using the above code keep the app in the background</p>