analysis fixes

 include: package:lint/analysis_options_package.yaml
+
+linter:
+  rules:
+    - combinators_ordering
+    - require_trailing_commas
+    - unnecessary_library_directive
\ No newline at end of file

-library mobile_scanner;
-
 export 'src/enums/camera_facing.dart';
 export 'src/enums/detection_speed.dart';
 export 'src/enums/mobile_scanner_error_code.dart';

-library mobile_scanner_web;
-
 export 'src/web/base.dart';
 export 'src/web/jsqr.dart';
 export 'src/web/zxing.dart';

@@ -19,7 +19,8 @@ class MobileScannerController {
     this.formats,
     this.returnImage = false,
     @Deprecated(
-        'Instead, use the result of calling `start()` to determine if permissions were granted.')
+      'Instead, use the result of calling `start()` to determine if permissions were granted.',
+    )
     this.onPermissionSet,
     this.autoStart = true,
   });

 import 'dart:async';
 import 'dart:html' as html;
-import 'dart:js' show context, JsObject;
+import 'dart:js' show JsObject, context;
 
 import 'package:mobile_scanner/src/web/base.dart';
 

@@ -7,12 +7,20 @@ void main() {
   TestWidgetsFlutterBinding.ensureInitialized();
 
   setUp(() {
-    channel.setMockMethodCallHandler((MethodCall methodCall) async {
+    TestDefaultBinaryMessengerBinding.instance.defaultBinaryMessenger
+        .setMockMethodCallHandler(
+      channel,
+      (MethodCall methodCall) async {
         return '42';
-    });
+      },
+    );
   });
 
   tearDown(() {
-    channel.setMockMethodCallHandler(null);
+    TestDefaultBinaryMessengerBinding.instance.defaultBinaryMessenger
+        .setMockMethodCallHandler(
+      channel,
+      null,
+    );
   });
 }