title: UI Automator Viewer: receiving "Error taking device screenshot: null" every time from AVD device
body: <p>This only happends on the AVD devices within the AVD manager.  I never get this error when capturing uiautomatorviewer screenshots from Genymotion.</p>
  
  <p>When attempting to capture within the Android Device Monitor in AS...it gives me a little more detail:
  Reason:
  Error obtaining UI hierarchy</p>
  
  <p><img src="https://i.stack.imgur.com/zig49.png" alt="enter image description here"></p>