[video_player] Update example app to replace ButtonBar with OverflowBar (#5274)

This PR replaces `ButtonBar` with `OverflowBar` in `video_player/example`  in preparation of `ButtonBar` deprecation.

Related to https://github.com/flutter/flutter/issues/127955

packages/video_player/video_player/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 2.8.1
+
+* Updates the example app: replaces `ButtonBar` with `OverflowBar` widget.
+
 ## 2.8.0
 
 * Adds support for macOS.

packages/video_player/video_player/example/lib/main.dart

@@ -121,21 +121,26 @@ class _ExampleCard extends StatelessWidget {
             leading: const Icon(Icons.airline_seat_flat_angled),
             title: Text(title),
           ),
-          ButtonBar(
-            children: <Widget>[
-              TextButton(
-                child: const Text('BUY TICKETS'),
-                onPressed: () {
-                  /* ... */
-                },
-              ),
-              TextButton(
-                child: const Text('SELL TICKETS'),
-                onPressed: () {
-                  /* ... */
-                },
-              ),
-            ],
+          Padding(
+            padding: const EdgeInsets.all(8.0),
+            child: OverflowBar(
+              alignment: MainAxisAlignment.end,
+              spacing: 8.0,
+              children: <Widget>[
+                TextButton(
+                  child: const Text('BUY TICKETS'),
+                  onPressed: () {
+                    /* ... */
+                  },
+                ),
+                TextButton(
+                  child: const Text('SELL TICKETS'),
+                  onPressed: () {
+                    /* ... */
+                  },
+                ),
+              ],
+            ),
           ),
         ],
       ),

packages/video_player/video_player/pubspec.yaml

@@ -3,7 +3,7 @@ description: Flutter plugin for displaying inline video with other Flutter
   widgets on Android, iOS, and web.
 repository: https://github.com/flutter/packages/tree/main/packages/video_player/video_player
 issue_tracker: https://github.com/flutter/flutter/issues?q=is%3Aissue+is%3Aopen+label%3A%22p%3A+video_player%22
-version: 2.8.0
+version: 2.8.1
 
 environment:
   sdk: ">=3.1.0 <4.0.0"