Add plugin and host registration to multiple_flutters example (#942)

add_to_app/multiple_flutters/multiple_flutters_ios/MultipleFluttersIos/SingleFlutterViewController.swift

@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 import Flutter
+import FlutterPluginRegistrant
 import Foundation
 
 /// A FlutterViewController intended for the MyApp widget in the Flutter module.
@@ -16,6 +17,7 @@ class SingleFlutterViewController: FlutterViewController, DataModelObserver {
   init(withEntrypoint entryPoint: String?) {
     let appDelegate: AppDelegate = UIApplication.shared.delegate as! AppDelegate
     let newEngine = appDelegate.engines.makeEngine(withEntrypoint: entryPoint, libraryURI: nil)
+    GeneratedPluginRegistrant.register(with: newEngine)
     super.init(engine: newEngine, nibName: nil, bundle: nil)
     DataModel.shared.addObserver(observer: self)
   }

add_to_app/multiple_flutters/multiple_flutters_ios/Podfile

@@ -1,11 +1,11 @@
-# Uncomment the next line to define a global platform for your project
-# platform :ios, '9.0'
+# Copyright 2021 The Flutter team. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
 
 flutter_application_path = '../multiple_flutters_module'
 load File.join(flutter_application_path, '.ios', 'Flutter', 'podhelper.rb')
 
 target 'MultipleFluttersIos' do
-  # Comment the next line if you don't want to use dynamic frameworks
   use_frameworks!
   install_all_flutter_pods(flutter_application_path)
 end

add_to_app/multiple_flutters/multiple_flutters_ios/Podfile.lock

@@ -2,13 +2,17 @@ PODS:
   - Flutter (1.0.0)
   - FlutterPluginRegistrant (0.0.1):
     - Flutter
+    - url_launcher
   - multiple_flutters_module (0.0.1):
     - Flutter
+  - url_launcher (0.0.1):
+    - Flutter
 
 DEPENDENCIES:
   - Flutter (from `../multiple_flutters_module/.ios/Flutter/engine`)
   - FlutterPluginRegistrant (from `../multiple_flutters_module/.ios/Flutter/FlutterPluginRegistrant`)
   - multiple_flutters_module (from `../multiple_flutters_module/.ios/Flutter`)
+  - url_launcher (from `../multiple_flutters_module/.ios/.symlinks/plugins/url_launcher/ios`)
 
 EXTERNAL SOURCES:
   Flutter:
@@ -17,12 +21,15 @@ EXTERNAL SOURCES:
     :path: "../multiple_flutters_module/.ios/Flutter/FlutterPluginRegistrant"
   multiple_flutters_module:
     :path: "../multiple_flutters_module/.ios/Flutter"
+  url_launcher:
+    :path: "../multiple_flutters_module/.ios/.symlinks/plugins/url_launcher/ios"
 
 SPEC CHECKSUMS:
   Flutter: bdfa2e8fe0e2880a2c6a58a0b1a8675c262a07af
-  FlutterPluginRegistrant: 2afd5ea46d3a949472c9b7da6462d8fbf7d8b16e
+  FlutterPluginRegistrant: d0de10c7c4fc31cc6b676a5965b96100f7c035f7
   multiple_flutters_module: fdf461a0e4225614d475110d85db6fd6de5aeff1
+  url_launcher: b6e016d912f04be9f5bf6e8e82dc599b7ba59649
 
-PODFILE CHECKSUM: d7f39981f450db398859f05de2475ec53909a487
+PODFILE CHECKSUM: 91c00dfcff6ea3b8d853bf0c2411672a01ca993c
 
-COCOAPODS: 1.10.1
+COCOAPODS: 1.11.2