private void updateGlobalDisplayStateLocked() {
   final int count = mDisplayDevices.size();
   for (int i = 0; i < count; i++) {
     DisplayDevice device = mDisplayDevices.get(i);
     updateDisplayStateLocked(device);
   }
 }
  private void handleDisplayDeviceAddedLocked(DisplayDevice device) {
    if (mDisplayDevices.contains(device)) {
      Slog.w(
          TAG,
          "Attempted to add already added display device: " + device.getDisplayDeviceInfoLocked());
      return;
    }

    Slog.i(TAG, "Display device added: " + device.getDisplayDeviceInfoLocked());

    mDisplayDevices.add(device);
    addLogicalDisplayLocked(device);
    updateDisplayStateLocked(device);
    scheduleTraversalLocked(false);
  }