Fixed ProgressIndicatorTheme.wrap() to just return a new ProgressIndicatorTheme. (#81359)

packages/flutter/lib/src/material/progress_indicator_theme.dart

@@ -177,8 +177,7 @@ class ProgressIndicatorTheme extends InheritedTheme {
 
   @override
   Widget wrap(BuildContext context, Widget child) {
-    final ProgressIndicatorTheme? ancestorTheme = context.findAncestorWidgetOfExactType<ProgressIndicatorTheme>();
-    return identical(this, ancestorTheme) ? child : ProgressIndicatorTheme(data: data, child: child);
+    return ProgressIndicatorTheme(data: data, child: child);
   }
 
   @override

packages/flutter/test/material/progress_indicator_test.dart

@@ -826,4 +826,35 @@ void main() {
       TargetPlatform.linux,
     }),
   );
+
+  testWidgets('ProgressIndicatorTheme.wrap() always creates a new ProgressIndicatorTheme', (WidgetTester tester) async {
+
+    late BuildContext builderContext;
+
+    const ProgressIndicatorThemeData themeData = ProgressIndicatorThemeData(
+      color: Color(0xFFFF0000),
+      linearTrackColor: Color(0xFF00FF00),
+    );
+
+    final ProgressIndicatorTheme progressTheme = ProgressIndicatorTheme(
+      data: themeData,
+      child: Builder(
+        builder: (BuildContext context) {
+          builderContext = context;
+          return const LinearProgressIndicator(value: 0.5);
+        }
+      ),
+    );
+
+    await tester.pumpWidget(MaterialApp(
+      home: progressTheme,
+    ));
+    final Widget wrappedTheme = progressTheme.wrap(builderContext, Container());
+
+    // Make sure the returned widget is a new ProgressIndicatorTheme instance
+    // with the same theme data as the original.
+    expect(wrappedTheme, isNot(equals(progressTheme)));
+    expect(wrappedTheme, isInstanceOf<ProgressIndicatorTheme>());
+    expect((wrappedTheme as ProgressIndicatorTheme).data, themeData);
+  });
 }