UPDATE

Samples/UIWidgetsSamples_2019_4/Assets/UIWidgetsGallery/demo/shrine/expanding_bottom_sheet.cs

     
 
     public class ExpandingBottomSheet : StatefulWidget {
-        public ExpandingBottomSheet(Key key = null, AnimationController hideController = null)
+        public ExpandingBottomSheet(
+          Key key = null, 
+          AnimationController hideController = null)
         : base(key: key)
         {
             D.assert(hideController != null);
     }
   }
 
-  Widget _buildThumbnails(int numProducts) {
-    return new Container(
-      child: new Opacity(
-        opacity: _thumbnailOpacityAnimation.value,
-        child: new Column(
-          children: new List<Widget>{
-            new Row(
-              children: new List<Widget>{
-                new AnimatedPadding(
-                  padding: _cartPaddingFor(numProducts),
-                  child: new Icon(Icons.shopping_cart),
-                  duration: TimeSpan.FromMilliseconds(225)
-                ),
-                new Container(
-                  // Accounts for the overflow number
-                  width: numProducts > 3 ? _width - 94.0f: _width - 64.0f,
-                  height: expanding_buttom_sheetUtils._kCartHeight,
-                  padding: EdgeInsets.symmetric(vertical: 8.0f),
-                  child: new ProductThumbnailRow()
-                ),
-                new ExtraProductsNumber(),
-              }
-            ),
-          }
-        )
+  Widget _buildThumbnails(int numProducts)
+  {
+    return new Opacity(
+      opacity: _thumbnailOpacityAnimation.value,
+      child: new Column(
+        children: new List<Widget>
+        {
+          new Row(
+            children: new List<Widget>
+            {
+             /* new AnimatedPadding(
+                padding: _cartPaddingFor(numProducts),
+                child: new Icon(Icons.shopping_cart),
+                duration: TimeSpan.FromMilliseconds(225)
+              ),*/
+              new Container(
+                // Accounts for the overflow number
+                width: numProducts > 3 ? _width - 94.0f : _width - 64.0f,
+                height: expanding_buttom_sheetUtils._kCartHeight,
+                padding: EdgeInsets.symmetric(vertical: 8.0f),
+                child: new ProductThumbnailRow()
+              )//, new ExtraProductsNumber(),
+            }
+          ),
+        }
       )
     );
   }
   }
 
   public readonly GlobalKey<AnimatedListState> listKey;
-
-  //public readonly Delegate removedItemBuilder;
   public RemovedItemBuilder removedItemBuilder;
   public readonly List<int> _items;
 

Samples/UIWidgetsSamples_2019_4/Assets/UIWidgetsGallery/gallery/app.cs

 namespace UIWidgetsGallery.gallery
 {
     public class GalleryApp : StatefulWidget
-    {
-        public GalleryApp(
+    { public GalleryApp(
             Key key = null,
             UpdateUrlFetcher updateUrlFetcher = null,
             bool enablePerformanceOverlay = true,
                                 // Specifically use a blank Cupertino theme here and do not transfer
                                 // over the Material primary color etc except the brightness to
                                 // showcase standard iOS looks.
-                                new Builder(builder: (BuildContext subsubContext) =>
+                                new Builder(builder: (BuildContext context1) =>
-                                            brightness: Theme.of(context).brightness
+                                            brightness: Theme.of(context1).brightness
                                         ),
                                         child: child
                                     );