title: Capture system.err
body: <p>I am trying to capture the error log that is printed when a test fails.</p>
  
  <p>I am able to get the normal log via </p>
  
  <pre><code>adb -s $device logcat System.out:I *:S
  </code></pre>
  
  <p>How do I also capture the exception thrown by a test failing?</p>