Update TextStyle.hashCode to handle list fields (#50520)

packages/flutter/lib/src/painting/text_style.dart

@@ -1177,7 +1177,6 @@ class TextStyle extends Diagnosticable {
       color,
       backgroundColor,
       fontFamily,
-      fontFamilyFallback,
       fontSize,
       fontWeight,
       fontStyle,
@@ -1191,8 +1190,9 @@ class TextStyle extends Diagnosticable {
       decoration,
       decorationColor,
       decorationStyle,
-      shadows,
-      fontFeatures,
+      hashList(shadows),
+      hashList(fontFeatures),
+      hashList(fontFamilyFallback),
     );
   }
 

packages/flutter/test/painting/text_style_test.dart

@@ -2,8 +2,9 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import 'dart:ui' as ui show TextStyle, ParagraphStyle;
+import 'dart:ui' as ui show TextStyle, ParagraphStyle, FontFeature, Shadow;
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/painting.dart';
 import '../flutter_test_alternative.dart';
 
@@ -256,6 +257,13 @@ void main() {
     expect(TextStyle.lerp(foo.merge(bar), baz, 0.51).copyWith().debugLabel, '(lerp((foo).merge(bar) ⎯0.5→ baz)).copyWith');
   });
 
+  test('TextStyle.hashCode', () {
+    const TextStyle a = TextStyle(fontFamilyFallback: <String>['Roboto'], shadows: <ui.Shadow>[ui.Shadow()], fontFeatures: <ui.FontFeature>[ui.FontFeature('abcd')]);
+    const TextStyle b = TextStyle(fontFamilyFallback: <String>['Noto'], shadows: <ui.Shadow>[ui.Shadow()], fontFeatures: <ui.FontFeature>[ui.FontFeature('abcd')]);
+    expect(a.hashCode, a.hashCode);
+    expect(a.hashCode, isNot(equals(b.hashCode)));
+  }, skip: kIsWeb);
+
   test('TextStyle foreground and color combos', () {
     const Color red = Color.fromARGB(255, 255, 0, 0);
     const Color blue = Color.fromARGB(255, 0, 0, 255);