Revert "exposed bridge in ReactNativeNavigation"

This reverts commit ee48da2e7c.

lib/ios/RNNControllerFactory.m

 	RNNRootViewController* component = [[RNNRootViewController alloc] initWithName:name withOptions:options withComponentId:componentId rootViewCreator:_creator eventEmitter:_eventEmitter isExternalComponent:NO];
 	if (!component.isCustomViewController) {
 		CGSize availableSize = UIApplication.sharedApplication.delegate.window.bounds.size;
-		[_bridge.uiManager setAvailableSize:availableSize forRootView:component.reactView];
+		[_bridge.uiManager setAvailableSize:availableSize forRootView:component.view];
 	}
 	return component;
 }