opt video bottomsheet

Signed-off-by: dom <githubaccount56556@proton.me>

lib/pages/video/widgets/header_control.dart

@@ -1247,7 +1247,7 @@ class HeaderControlState extends State<HeaderControl>
   /// 字幕设置
   void showSetSubtitle() {
     showBottomSheet(
-      padding: isFullScreen ? 70 : null,
+      padding: () => isFullScreen ? const .only(bottom: 70) : .zero,
       (context, setState) {
         final theme = Theme.of(context);
 

lib/pages/video/widgets/header_mixin.dart

@@ -14,12 +14,11 @@ mixin HeaderMixin<T extends StatefulWidget> on State<T> {
 
   Future<void>? showBottomSheet(
     StatefulWidgetBuilder builder, {
-    double? padding,
+    ValueGetter<EdgeInsets>? padding,
   }) {
     return PageUtils.showVideoBottomSheet(
       context,
       maxWidth: 512,
-      isFullScreen: () => isFullScreen,
       padding: padding,
       child: StatefulBuilder(
         builder: (context, setState) => plPlayerController.darkVideoPage