a === b -> identical(a, b)

tests/language/class_literal_test.dart

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 // Test that classes cannot be used as expressions.
 
 class Class {
   static fisk() => 42;
 }
 
@@ skipping 13 matching lines @@
     var x = Class[0]; /// 10: compile-time error
     var x = Class[0].field; /// 11: compile-time error
     var x = Class[0].method(); /// 12: compile-time error
     foo(Class); /// 13: compile-time error
     foo(Class()); /// 14: compile-time error
     foo(Class.method()); /// 15: static type warning
     foo(Class.field); /// 16: static type warning
     foo(Class[0]); /// 17: compile-time error
     foo(Class[0].field); /// 18: compile-time error
     foo(Class[0].method()); /// 19: compile-time error
-    Class === null; /// 20: compile-time error
-    null === Class; /// 21: compile-time error
+    Class == null; /// 20: compile-time error
+    null == Class; /// 21: compile-time error
     Class[0] = 91; /// 22: compile-time error
     Class++; /// 23: compile-time error
     ++Class; /// 24: compile-time error
     Class / 3; /// 25: compile-time error
     Class += 3; /// 26: compile-time error
     Class[0] += 3; /// 27: compile-time error
     ++Class[0]; /// 28: compile-time error
     Class[0]++; /// 29: compile-time error
   }
   Expect.equals(42, Class.fisk());
   Expect.equals(null, foo(Class.fisk()));
 }