iOS support for "background" sync

ios/Runner/AppDelegate.swift

@@ -8,6 +8,16 @@ import Flutter
     didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?
   ) -> Bool {
     GeneratedPluginRegistrant.register(with: self)
+
+    SwiftFlutterForegroundTaskPlugin.setPluginRegistrantCallback(registerPlugins)
+    if #available(iOS 10.0, *) {
+        UNUserNotificationCenter.current().delegate = self as? UNUserNotificationCenterDelegate
+    }
+
     return super.application(application, didFinishLaunchingWithOptions: launchOptions)
   }
 }
+
+func registerPlugins(registry: FlutterPluginRegistry) {
+  GeneratedPluginRegistrant.register(with: registry)
+}

ios/Runner/Runner-Bridging-Header.h

@@ -1 +1,3 @@
 #import "GeneratedPluginRegistrant.h"
+#import <flutter_foreground_task/FlutterForegroundTaskPlugin.h>
+