Flutter作为iOS项目的module，webview_flutter无法加载网页问题解决

报错：

Unhandled Exception: PlatformException(unregistered_view_type, trying to create a view with an unregistered type, unregistered view type: 'plugins.flutter.io/webview')
#0      StandardMethodCodec.decodeEnvelope (package:flutter/src/services/message_codecs.dart:569:7)
#1      MethodChannel.invokeMethod (package:flutter/src/services/platform_channel.dart:316:33)
<asynchronous suspension>
#2      PlatformViewsService.initUiKitView (package:flutter/src/services/platform_views.dart:168:41)
<asynchronous suspension>
#3      _UiKitViewState._createNewUiKitView (package:flutter/src/widgets/platform_view.dart:503:71)
<asynchronous suspension>
#4      _UiKitViewState._initializeOnce (package:flutter/src/widgets/platform_view.dart:453:5)
#5      _UiKitViewState.didChangeDependencies (package:flutter/src/widgets/platform_view.dart:463:5)
#6      StatefulElement._firstBuild (package:flutter/src/widgets/framework.dart:4079:12)
#7      ComponentElement.mount (package:flutter/src/widgets/framework.dart:3912:5)
#8      Element.inflateWidget (package:flutter/src/widgets/framework.dart:3094:14)
#9      Element.updateChild (package:flutter/src/widgets/framework.dart:2897:12)
#10     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3954:16)
#11     Element.rebuild (package:flutter/src/widgets/framework.dart:3731:5)

解决办法：
flutter plugin注册的问题，在自定义的viewcontroller中重新注册即可解决。
参考Flutter开发填坑记录

AppViewController.h

#import <Flutter/Flutter.h>

@interface AppViewController : FlutterViewController {

}

@end

AppViewController.m

#import "AppViewController.h"
#import <FlutterPluginRegistrant/GeneratedPluginRegistrant.h>

@implementation AppViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    // 解决Plugin注册问题，导致flutter的插件失败，比如webview_flutterd无法显示网页
    [GeneratedPluginRegistrant registerWithRegistry:self];
}