title: Copying text to clipboard leads to crash on parallel tests execution on emulators
body: <p>Running test on appium android on several emulators. Using ThreadLocal to separate driver instances.
  Faced with problem when one of emulators always crashes on the same step.</p>
  <p>After investigating I came to the conclusion that the reason is clipboard. One emulator clicks on the clipboard field and after some time the second do the same and crashes.</p>
  <p>Java exception:</p>
  <pre><code>org.openqa.selenium.WebDriverException: An unknown server-side error occurred while processing the command. Original error: Could not proxy command to the remote server. Original error: socket hang up
  </code></pre>
  <p>Adb logs:</p>
  <pre><code>*** FATAL EXCEPTION IN SYSTEM PROCESS
    java.lang.IllegalStateException: beginBroadcast() called while already in a broadcast
      at android.os.RemoteCallbackList.beginBroadcast(RemoteCallbackList.java:241)
      at com.android.server.clipboard.ClipboardService.setPrimaryClipInternal(ClipboardService.java:583)
      at com.android.server.clipboard.ClipboardService$1.onHostClipboardUpdated(ClipboardService.java:205)
      at com.android.server.clipboard.HostClipboardMonitor.run(ClipboardService.java:125)
      at java.lang.Thread.run(Thread.java:919)
  </code></pre>
  <p>So my question is:</p>
  <ol>
  <li>Whether it is possible to disable saving anything to clipboard using adb or appium command?</li>
  <li>Whether it is possible to clear it so it would be a kind of resetting?</li>
  <li>Or maybe there is a decision in the multithreading area?</li>
  <li>Any other ways?</li>
  </ol>
  <p>Thanks for help.</p>