[url_launcher] forceSafariVC should be nullable to avoid breaking change (flutter#3354)

Author: mehmetf

packages/url_launcher/url_launcher/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 6.0.0-nullsafety.3
+
+* forceSafariVC should be nullable.
+
 ## 6.0.0-nullsafety.2
 
 * Fix outdated links across a number of markdown files ([#3276](https://github.com/flutter/plugins/pull/3276))

packages/url_launcher/url_launcher/lib/url_launcher.dart

@@ -62,7 +62,7 @@ import 'package:url_launcher_platform_interface/url_launcher_platform_interface.
 /// is set to true and the universal link failed to launch.
 Future<bool> launch(
   String urlString, {
-  bool forceSafariVC = true,
+  bool? forceSafariVC,
   bool forceWebView = false,
   bool enableJavaScript = false,
   bool enableDomStorage = false,
@@ -95,7 +95,7 @@ Future<bool> launch(
 
   final bool result = await UrlLauncherPlatform.instance.launch(
     urlString,
-    useSafariVC: forceSafariVC,
+    useSafariVC: forceSafariVC ?? isWebURL,
     useWebView: forceWebView,
     enableJavaScript: enableJavaScript,
     enableDomStorage: enableDomStorage,

packages/url_launcher/url_launcher/pubspec.yaml

@@ -2,7 +2,7 @@ name: url_launcher
 description: Flutter plugin for launching a URL on Android and iOS. Supports
   web, phone, SMS, and email schemes.
 homepage: https://github.com/flutter/plugins/tree/master/packages/url_launcher/url_launcher
-version: 6.0.0-nullsafety.2
+version: 6.0.0-nullsafety.3
 
 flutter:
   plugin: