Improvements to SearchDelegate (#91982)

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

@@ -581,7 +581,7 @@ class _SearchPageState<T> extends State<_SearchPage<T>> {
             title: TextField(
               controller: widget.delegate._queryTextController,
               focusNode: focusNode,
-              style: theme.textTheme.headline6,
+              style: widget.delegate.searchFieldStyle ?? theme.textTheme.headline6,
               textInputAction: widget.delegate.textInputAction,
               keyboardType: widget.delegate.keyboardType,
               onSubmitted: (String _) {

packages/flutter/test/material/search_test.dart

@@ -554,8 +554,13 @@ void main() {
     await tester.pumpAndSettle();
 
     final Text hintText = tester.widget(find.text(searchHintText));
+    final TextField textField = tester.widget<TextField>(find.byType(TextField));
+
     expect(hintText.style?.color, delegate.searchFieldStyle?.color);
     expect(hintText.style?.fontSize, delegate.searchFieldStyle?.fontSize);
+    expect(textField.style?.color, delegate.searchFieldStyle?.color);
+    expect(textField.style?.fontSize, delegate.searchFieldStyle?.fontSize);
+
   });
 
   testWidgets('keyboard show search button by default', (WidgetTester tester) async {