fix(flutter): 更多面板增加小窗播放入口

test/player/player_fullscreen_test.dart

@@ -389,7 +389,6 @@ void main() {
       Key('player-more-text-size'),
       Key('player-more-cast'),
       Key('player-more-timer'),
-      Key('player-more-pip'),
       Key('player-more-report'),
     ]) {
       expect(find.byKey(removed), findsNothing);
@@ -506,6 +505,30 @@ void main() {
     expect(find.text('720P · Unavailable'), findsOneWidget);
   });
 
+  testWidgets('should_show_pip_action_when_platform_supported', (tester) async {
+    await _pumpApp(tester);
+    await _openSeriesPlayer(tester);
+    await tester.tap(find.byKey(const Key('player-more')));
+    await tester.pumpAndSettle();
+
+    expect(find.byKey(const Key('player-more-pip')), findsOneWidget);
+    expect(find.byKey(const Key('player-more-clear')), findsOneWidget);
+    expect(find.byKey(const Key('player-more-offline')), findsOneWidget);
+  }, variant: TargetPlatformVariant.only(TargetPlatform.android));
+
+  testWidgets('should_hide_pip_action_when_platform_unsupported', (
+    tester,
+  ) async {
+    await _pumpApp(tester);
+    await _openSeriesPlayer(tester);
+    await tester.tap(find.byKey(const Key('player-more')));
+    await tester.pumpAndSettle();
+
+    expect(find.byKey(const Key('player-more-pip')), findsNothing);
+    expect(find.byKey(const Key('player-more-clear')), findsOneWidget);
+    expect(find.byKey(const Key('player-more-offline')), findsOneWidget);
+  }, variant: TargetPlatformVariant.only(TargetPlatform.macOS));
+
   testWidgets('should_enter_clear_screen_from_more_panel', (tester) async {
     await _pumpApp(tester);
     await _openSeriesPlayer(tester);