public static void tapDialogNegativeButton(Instrumentation instrumentation) {
    selectDialogButton(instrumentation);

    instrumentation.sendKeyDownUpSync(KeyEvent.KEYCODE_DPAD_LEFT);
    instrumentation.sendKeyDownUpSync(KeyEvent.KEYCODE_DPAD_CENTER);
  }
Taps the negative button of a currently displayed dialog. This method assumes that a button of
the dialog is currently selected.

@see #tapDialogPositiveButton(Instrumentation)
javatests/com/google/android/apps/authenticator/testing/TestUtilities.java