fix IComparable interface

use the buildin IComparable in C#

com.unity.uiwidgets/Runtime/widgets/animated_list.cs

             while (min < max) {
                 int mid = min + ((max - min) >> 1);
                 T element = sortedList[mid];
-                int comp = element.compareTo(value);
+                int comp = element.CompareTo(value);
                 if (comp == 0) {
                     return mid;
                 }
         }
     }
 
-    public class _ActiveItem  : Comparable<_ActiveItem> {
+    public class _ActiveItem  : IComparable {
         
         public _ActiveItem(
             AnimationController controller,
         public int itemIndex;
 
 
-        public int compareTo(_ActiveItem other) {
-       
-            return itemIndex - other.itemIndex;
-        }
-
-        public int compare(Comparable<_ActiveItem> a, _ActiveItem b) {
-            return 0;
-            //throw new NotImplementedException();
+        public int CompareTo(object other) {
+            D.assert(GetType() == other.GetType());
+            return itemIndex - ((_ActiveItem)other).itemIndex;
         }
     }
     public class AnimatedList : StatefulWidget {

com.unity.uiwidgets/Runtime/widgets/focus_traversal.cs

             return sortedList;
         }
     }
-    
-    public interface Comparable<T> {
-      
-        int compareTo(T other);
-        int compare(Comparable<T> a, T b);
-    }
-    public abstract class FocusOrder : Diagnosticable , Comparable<FocusOrder> {
+    public abstract class FocusOrder : Diagnosticable , IComparable {
-        public int compareTo(FocusOrder other) {
+        public int CompareTo(object other) {
-            return doCompare(other);
-        }
-
-        public int compare(Comparable<FocusOrder> a, FocusOrder b) {
-            //throw new NotImplementedException();
-            return a.compareTo(b);
+            return doCompare((FocusOrder) other);
         }
 
         protected abstract int doCompare(FocusOrder other);
                 "Incompatible order types can't be compared.  Use a FocusTraversalGroup to group " +
                 "similar orders together."
               ); 
-                return a.order.compareTo(b.order); 
+                return a.order.CompareTo(b.order); 
             }); 
             return ordered.Select((_OrderedFocusInfo info) => info.node).Concat(unordered);
         }