title: Activity_A start Activity_B with SINGLE_TOP, but Activity_B is created in new task, not in Activity_A's task?
body: <p>Activity_A is in appA, and Activity_B is in appB(Android Settings Activity).
  I click a item in Activity_A to start Activity_B like this:</p>
  
  <pre><code>  intent.setFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP);
    mContext.startActivity(intent);
  </code></pre>
  
  <p>mContext is Activity_A.</p>
  
  <p>In some articles, say that activity will push into same task which activity start it.  But Activity_B create a new task, not in Activity_A's task.
  Anyone Help me?</p>