code: private static BroadcastReceiver registerBroadcastReceiverInternal(final Context context,
                                                                         final String action, final BroadcastReceiver receiver) {
          if (receiver == null) {
              return null;
          }
  
          IntentFilter filter = new IntentFilter(action);
          context.registerReceiver(receiver, filter);
          return receiver;
      }
docs: Register broadcast receiver internal.
  
  @param context
  the context
  @param action
  the action
  @param receiver
  the receiver
  
  @return the broadcast receiver