Native NullReferenceException thrown on ByMatcher.java:142 when using Android 4.4.x devices.

Hi everyone,

I'm trying to include an Android 4 device for my Automation suite, but for some reason I'm seeing NullReference exceptions when interacting with certain textboxes in an app under test but ONLY when using pre-Android 5 devices.

The stack traces I'm seeing are as follows:

`java.lang.NullPointerException
at android.support.test.uiautomator.ByMatcher.findMatches(ByMatcher.java:142)
at android.support.test.uiautomator.ByMatcher.findMatches(ByMatcher.java:111)
at android.support.test.uiautomator.ByMatcher.findMatches(ByMatcher.java:96)
at android.support.test.uiautomator.UiDevice.findObjects(UiDevice.java:171)`

when using FindObjects method to look for the textbox in question or:

`java.lang.NullPointerException
at android.support.test.uiautomator.ByMatcher.findMatches(ByMatcher.java:142)
at android.support.test.uiautomator.ByMatcher.findMatches(ByMatcher.java:111)
at android.support.test.uiautomator.ByMatcher.findMatch(ByMatcher.java:72)
at android.support.test.uiautomator.UiDevice.hasObject(UiDevice.java:154)
at android.support.test.uiautomator.Until$2.apply(Until.java:55)
at android.support.test.uiautomator.Until$2.apply(Until.java:52)
at android.support.test.uiautomator.WaitMixin.wait(WaitMixin.java:40)
at android.support.test.uiautomator.WaitMixin.wait(WaitMixin.java:34)
at android.support.test.uiautomator.UiDevice.wait(UiDevice.java:187)`

when using phone.wait(Until.hasObject(By.res(identifier)), timer); for example.

Any clues on how to bypass this issue? I'm not sure if our App developers are doing something strange with these textboxes or early Android versions are just poorly supported by UiAutomator.

Comienza reproduciendo el fallo en un dispositivo con una versión de Android anterior a Android 5 mediante UiDevice.findObjects y wait(Until.hasObject(By.res(identifier))). Después inspecciona ByMatcher.java:142 y sus llamadores para determinar por qué aparece el valor null; se considerará terminado cuando se documente una solución alternativa fiable o se proporcione un fix validado frente a ambas rutas de llamada afectadas.

Escrito por el modelo de indexación a partir del texto del issue.