Remove redundant static fields to reduce memory usage

Author: lindexi

src/Microsoft.DotNet.Wpf/src/System.Xaml/System/Xaml/Schema/XamlTypeInvoker.cs

@@ -17,7 +17,6 @@ namespace System.Xaml.Schema
     public class XamlTypeInvoker
     {
         private static XamlTypeInvoker s_Unknown;
-        private static object[] s_emptyObjectArray = Array.Empty<object>();
 
         private Dictionary<XamlType, MethodInfo> _addMethods;
         internal MethodInfo EnumeratorMethod { get; set; }
@@ -223,7 +222,7 @@ public virtual IEnumerator GetItems(object instance)
                 throw new NotSupportedException(SR.OnlySupportedOnCollectionsAndDictionaries);
             }
             MethodInfo getEnumMethod = GetEnumeratorMethod();
-            return (IEnumerator)getEnumMethod.Invoke(instance, s_emptyObjectArray);
+            return (IEnumerator)getEnumMethod.Invoke(instance, Array.Empty<object>());
         }
 
         // vvvvv---- Unused members.  Servicing policy is to retain these anyway.  -----vvvvv