title: UIContainerView with intrinsic size placeholder values for AutoLayout doesn't receive events?
body: <p>This is with Xcode 7.0 beta 6 (7A192o). It seems that specifying an intrinsic size placeholder values for a UIContainerView causes it not to receive events.</p>
  
  <ol>
  <li>Create a standard single view application.</li>
  <li>In the view, insert a UIContainerView (center it with Auto Layout)</li>
  <li>Embed a simple button into the UIContainerView.</li>
  <li>Run the simulator and observe that if you click on the button you can see that it responds (dims)</li>
  <li>Stop the the simulator and add intrinsic size placeholders for the UIContainerView.</li>
  <li>Run the simulator and observe that if you click on the button you no longer see that it responds (dims).</li>
  <li>Stop the simulator and either remove intrinsic size placeholders or set them to NONE.</li>
  <li>Run the simulator and observe that if you click on the button you can see that it responds again.</li>
  </ol>
  
  <p>No warnings/errors appear in the log.</p>
  
  <p>I've uploaded a video of this behavior <a href="https://youtu.be/wFinyMk3hvw" rel="nofollow">here</a>. Am I doing something wrong or is this a bug? I'm rather new to auto-layouts so I want to check if I am doing something wrongly before filing a bug with Apple.</p>