Adds missing `style` to `PopupMenuButton` (#143392)

Adds missing `style` to `PopupMenuButton`.

Fixes: #114709

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

@@ -7,6 +7,7 @@ import 'package:flutter/rendering.dart';
 import 'package:flutter/scheduler.dart';
 import 'package:flutter/widgets.dart';
 
+import 'button_style.dart';
 import 'color_scheme.dart';
 import 'colors.dart';
 import 'constants.dart';
@@ -1149,6 +1150,7 @@ class PopupMenuButton<T> extends StatefulWidget {
     this.clipBehavior = Clip.none,
     this.useRootNavigator = false,
     this.popUpAnimationStyle,
+    this.style,
   }) : assert(
          !(child != null && icon != null),
          'You can only pass [child] or [icon], not both.',
@@ -1343,6 +1345,15 @@ class PopupMenuButton<T> extends StatefulWidget {
   /// If this is null, then the default animation will be used.
   final AnimationStyle? popUpAnimationStyle;
 
+  /// Customizes this icon button's appearance.
+  ///
+  /// The [style] is only used for Material 3 [IconButton]s. If [ThemeData.useMaterial3]
+  /// is set to true, [style] is preferred for icon button customization, and any
+  /// parameters defined in [style] will override the same parameters in [IconButton].
+  ///
+  /// Null by default.
+  final ButtonStyle? style;
+
   @override
   PopupMenuButtonState<T> createState() => PopupMenuButtonState<T>();
 }
@@ -1455,6 +1466,7 @@ class PopupMenuButtonState<T> extends State<PopupMenuButton<T>> {
       tooltip: widget.tooltip ?? MaterialLocalizations.of(context).showMenuTooltip,
       onPressed: widget.enabled ? showButtonMenu : null,
       enableFeedback: enableFeedback,
+      style: widget.style,
     );
   }
 }

packages/flutter/test/material/popup_menu_test.dart

@@ -4060,6 +4060,33 @@ void main() {
     expect(listViewportBounds.bottomRight.dy, lessThanOrEqualTo(windowSize.height));
     expect(listViewportBounds, overlaps(buttonBounds));
   });
+
+  testWidgets('PopupMenuButton honors style', (WidgetTester tester) async {
+    await tester.pumpWidget(
+      MaterialApp(
+        home: Scaffold(
+          body: PopupMenuButton<int>(
+            style: const ButtonStyle(
+              iconColor: MaterialStatePropertyAll<Color>(Colors.red),
+            ),
+            itemBuilder: (BuildContext context) {
+              return <PopupMenuItem<int>>[
+                const PopupMenuItem<int>(
+                  value: 1,
+                  child: Text('One'),
+                ),
+              ];
+            },
+          ),
+        ),
+      ),
+    );
+    final RichText iconText = tester.firstWidget(find.descendant(
+      of: find.byType(PopupMenuButton<int>),
+      matching: find.byType(RichText),
+    ));
+    expect(iconText.text.style?.color, Colors.red);
+  });
 }
 
 Matcher overlaps(Rect other) => OverlapsMatcher(other);