sliver safe area

Runtime/widgets/safe_area.cs

-using UnityEngine;
+using UnityEngine;
 
 namespace Unity.UIWidgets.widgets {
     public class SafeArea : StatelessWidget {
                     child: this.child));
         }
 
+
+        public override void debugFillProperties(DiagnosticPropertiesBuilder properties) {
+            base.debugFillProperties(properties);
+            properties.add(new FlagProperty("left", value: this.left, ifTrue: "avoid left padding"));
+            properties.add(new FlagProperty("top", value: this.top, ifTrue: "avoid top padding"));
+            properties.add(new FlagProperty("right", value: this.right, ifTrue: "avoid right padding"));
+            properties.add(new FlagProperty("bottom", value: this.bottom, ifTrue: "avoid bottom padding"));
+        }
+    }
+
+
+    class SliverSafeArea : StatelessWidget {
+        public SliverSafeArea(
+            Key key = null,
+            bool left = true,
+            bool top = true,
+            bool right = true,
+            bool bottom = true,
+            EdgeInsets minimum = null,
+            Widget sliver = null) : base(key: key) {
+            D.assert(sliver != null);
+            this.left = left;
+            this.top = top;
+            this.right = right;
+            this.bottom = bottom;
+            this.minimum = minimum ?? EdgeInsets.zero;
+            this.sliver = sliver;
+        }
+
+        public readonly bool left;
+
+        public readonly bool top;
+
+        public readonly bool right;
+
+        public readonly bool bottom;
+
+        public readonly EdgeInsets minimum;
+
+        public readonly Widget sliver;
+
+        public override Widget build(BuildContext context) {
+            EdgeInsets padding = MediaQuery.of(context).padding;
+            return new SliverPadding(
+                padding: EdgeInsets.only(
+                    left: Mathf.Max(this.left ? padding.left : 0.0f, this.minimum.left),
+                    top: Mathf.Max(this.top ? padding.top : 0.0f, this.minimum.top),
+                    right: Mathf.Max(this.right ? padding.right : 0.0f, this.minimum.right),
+                    bottom: Mathf.Max(this.bottom ? padding.bottom : 0.0f, this.minimum.bottom)
+                ),
+                sliver: MediaQuery.removePadding(
+                    context: context,
+                    removeLeft: this.left,
+                    removeTop: this.top,
+                    removeRight: this.right,
+                    removeBottom: this.bottom,
+                    child: this.sliver));
+        }
 
         public override void debugFillProperties(DiagnosticPropertiesBuilder properties) {
             base.debugFillProperties(properties);