@Override public void addBridgeIdleDebugListener(NotThreadSafeBridgeIdleDebugListener listener){
  mBridgeIdleListeners.add(listener);
}

@ Override public void addBridgeIdleDebugListener ( NotThreadSafeBridgeIdleDebugListener listener ) { mBridgeIdleListeners . add ( listener ) ; }
adds a idle listener for this catalyst instance . the listener will receive notifications whenever the bridge transitions from idle to busy and vice - versa , where the busy state is defined as there being some non - zero number of calls to js that haven ' t resolved via a onbatchcomplete call . the listener should be purely passive and not affect application logic .
