Fix skwasm's canvasDrawArc declaration and write tests.

lib/web_ui/lib/src/engine/skwasm/skwasm_impl/raw/raw_canvas.dart

@@ -108,7 +108,7 @@ external void canvasDrawCircle(
     CanvasHandle canvas, double x, double y, double radius, PaintHandle paint);
 
 @Native<Void Function(CanvasHandle, RawRect, Float, Float, Bool, PaintHandle)>(
-    symbol: 'canvas_drawCircle', isLeaf: true)
+    symbol: 'canvas_drawArc', isLeaf: true)
 external void canvasDrawArc(
     CanvasHandle canvas,
     RawRect rect,

lib/web_ui/test/ui/canvas_curves_golden_test.dart

@@ -0,0 +1,74 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'dart:math' as math;
+
+import 'package:test/bootstrap/browser.dart';
+import 'package:test/test.dart';
+import 'package:ui/ui.dart';
+import 'package:web_engine_tester/golden_tester.dart';
+
+import 'utils.dart';
+
+void main() {
+  internalBootstrapBrowserTest(() => testMain);
+}
+
+Future<void> testMain() async {
+  setUpUiTest();
+
+  const Rect region = Rect.fromLTWH(0, 0, 300, 300);
+
+  test('draw arc', () async {
+    final PictureRecorder recorder = PictureRecorder();
+    final Canvas canvas = Canvas(recorder, region);
+    canvas.drawArc(
+      const Rect.fromLTRB(100, 100, 200, 200),
+      math.pi / 3.0,
+      4.0 * math.pi / 3.0,
+      false,
+      Paint()
+        ..style = PaintingStyle.stroke
+        ..strokeWidth = 3.0
+        ..color = const Color(0xFFFF00FF)
+    );
+
+    await drawPictureUsingCurrentRenderer(recorder.endRecording());
+
+    await matchGoldenFile('ui_canvas_draw_arc.png', region: region);
+  });
+
+  test('draw circle', () async {
+    final PictureRecorder recorder = PictureRecorder();
+    final Canvas canvas = Canvas(recorder, region);
+    canvas.drawCircle(
+      const Offset(150, 150),
+      50,
+      Paint()
+        ..style = PaintingStyle.stroke
+        ..strokeWidth = 3.0
+        ..color = const Color(0xFFFF0000)
+    );
+
+    await drawPictureUsingCurrentRenderer(recorder.endRecording());
+
+    await matchGoldenFile('ui_canvas_draw_circle.png', region: region);
+  });
+
+  test('draw oval', () async {
+    final PictureRecorder recorder = PictureRecorder();
+    final Canvas canvas = Canvas(recorder, region);
+    canvas.drawOval(
+      const Rect.fromLTRB(100, 125, 200, 175),
+      Paint()
+        ..style = PaintingStyle.stroke
+        ..strokeWidth = 3.0
+        ..color = const Color(0xFF00FFFF)
+    );
+
+    await drawPictureUsingCurrentRenderer(recorder.endRecording());
+
+    await matchGoldenFile('ui_canvas_draw_oval.png', region: region);
+  });
+}