title: Android P displaying API compatibility error message
body: <p>Running an app built against SDK level 27 on Android P somewhat unpredictably displays the following dialog (the dialog title is the name of the application):</p>
  
  <p><a href="https://i.stack.imgur.com/8U6SP.png" rel="noreferrer"><img src="https://i.stack.imgur.com/8U6SP.png" alt="Mysterious dialog"></a></p>
  
  <blockquote>
    <p>Detected problems with API compatibility (visit g.co/dev/appcompat for more info)</p>
  </blockquote>
  
  <p>The URL leads to <a href="https://developer.android.com/preview/restrictions-non-sdk-interfaces" rel="noreferrer">this page about restrictions on non-SDK interfaces</a>. My application doesn't use reflection itself, but it does use Gson.</p>
  
  <p>There are no immediately obvious log messages in Logcat, except may messages such as:</p>
  
  <blockquote>
    <p>Accessing hidden field Landroid/widget/AbsListView;->mIsChildViewEnabled:Z (light greylist, reflection)</p>
  </blockquote>