title: UiScrollable not work in Android uiautomator
body: <p>Does anyone try the android <code>UITesting</code> framework <code>UIAutomator</code>?
  When I use the class <code>UiScrollabl</code>" to find some objects in a <em>scrollable</em> object, it can't find the object if the the length of the <em>scrollable</em> object is too long(need to swipe twice to find it), like "Developer options" in the "Settings" app.
  Does anyone have the same issue?</p>