fix lint wanring

Author: avenwu

analysis_options.yaml

@@ -6,5 +6,4 @@ include: package:pedantic/analysis_options.yaml
 analyzer:
   exclude:
     - example/**
-  enable-experiment:
-    - non-nullable
+    - test/**

lib/src/painter.dart

@@ -15,7 +15,6 @@
  */
 
 import 'package:flutter/material.dart';
-import 'package:flutter/widgets.dart';
 
 import 'convex_shape.dart';
 import 'reused_gradient.dart';

lib/src/style/fixed_circle_tab_style.dart

@@ -14,7 +14,6 @@
  *  limitations under the License.
  */
 
-import 'dart:ui';
 import 'package:flutter/material.dart';
 
 import '../item.dart';

lib/src/style/fixed_tab_style.dart

@@ -14,8 +14,6 @@
  *  limitations under the License.
  */
 
-import 'dart:ui';
-
 import 'package:flutter/material.dart';
 
 import '../item.dart';

lib/src/style/inner_builder.dart

@@ -14,8 +14,6 @@
  *  limitations under the License.
  */
 
-import 'dart:ui';
-
 import 'package:flutter/cupertino.dart';
 
 import '../bar.dart';

lib/src/style/transition_container_builder.dart

@@ -16,7 +16,6 @@
 
 import 'dart:math';
 
-import 'package:flutter/animation.dart';
 import 'package:flutter/cupertino.dart';
 
 import 'transition_container.dart';

test/widget_test.dart

@@ -145,10 +145,10 @@ void main() {
         )),
         Duration(milliseconds: 300),
       );
-      await tester.tap(find.byIcon(Icons.near_me).first);
+      await tester.tap(find.byIcon(Icons.near_me).first, warnIfMissed: false);
       await tester.pumpAndSettle(Duration(milliseconds: 300));
-      await tester.drag(find.byType(ConvexAppBar), Offset(200, 0));
-      await tester.drag(find.byType(ConvexAppBar), Offset(-200, 0));
+      await tester.drag(find.byType(ConvexAppBar), Offset(200, 0), warnIfMissed: false);
+      await tester.drag(find.byType(ConvexAppBar), Offset(-200, 0), warnIfMissed: false);
       await tester.pumpAndSettle(Duration(milliseconds: 300));
       await tester.startGesture(Offset(0, 100)).then((g) {
         return g.moveTo(Offset(500, 100));
@@ -182,7 +182,7 @@ void main() {
         ),
       )),
     );
-    await tester.tap(find.byIcon(Icons.near_me).first);
+    await tester.tap(find.byIcon(Icons.near_me).first, warnIfMissed: false);
   });
 
   testWidgets('Test tab controller', (WidgetTester tester) async {