dispose method

Implementation

@override
void dispose() {
  if (_disposed) {
    return;
  }
  if (identical(FlutterError.onError, _handleFlutterError)) {
    FlutterError.onError = _previousFlutterErrorHandler;
  }
  if (identical(PlatformDispatcher.instance.onError, _handlePlatformError)) {
    PlatformDispatcher.instance.onError = _previousPlatformErrorHandler;
  }
  if (_installedDebugPrintOverride &&
      identical(debugPrint, _handleDebugPrint)) {
    debugPrint = _previousDebugPrint ?? debugPrintThrottled;
  }
  _disposed = true;
}