Fix pasting or duplicating Multi Blend nodes

Source/Editor/Surface/SurfaceNode.cs

@@ -1001,6 +1001,15 @@ namespace FlaxEditor.Surface
             _isDuringValuesEditing = value;
         }
 
+        /// <summary>
+        /// Sets teh node values from the given pasted source. Can be overriden to perform validation or custom values processing.
+        /// </summary>
+        /// <param name="values">The input values array.</param>
+        public virtual void SetValuesPaste(object[] values)
+        {
+            Values = values;
+        }
+
         /// <summary>
         /// Called when node values set gets changed.
         /// </summary>