Reapply change to update dart2js operator equals semantics to follow

tests/compiler/dart2js_extra/operator_equals_test.dart

Index: tests/compiler/dart2js_extra/operator_equals_test.dart
diff --git a/tests/compiler/dart2js_extra/operator_equals_test.dart b/tests/compiler/dart2js_extra/operator_equals_test.dart
index 130af4a080f84fcf3c3a07bfff8a48ab45a99f1e..036827131ce8c2f3b7988d0284092f16c3f3a2c3 100644
--- a/tests/compiler/dart2js_extra/operator_equals_test.dart
+++ b/tests/compiler/dart2js_extra/operator_equals_test.dart
@@ -13,9 +13,9 @@ class AlwaysFalse {
 main() {
   var a = new AlwaysTrue();
   Expect.isTrue(a == 2);
-  Expect.isTrue(a == null);
+  Expect.isFalse(a == null);
   Expect.isFalse(a != 2);
-  Expect.isFalse(a != null);
+  Expect.isTrue(a != null);
 
   a = new AlwaysFalse();
   Expect.isFalse(a == 2);