Fixing core exception tests after Chrome update.

sdk/lib/_internal/compiler/implementation/lib/js_helper.dart

Index: sdk/lib/_internal/compiler/implementation/lib/js_helper.dart
diff --git a/sdk/lib/_internal/compiler/implementation/lib/js_helper.dart b/sdk/lib/_internal/compiler/implementation/lib/js_helper.dart
index 7a4cc611886bf97a38255b4a29897c47f72c7f1b..39e1c5c8f651b7254d2ac1d00b522d3925ff7525 100644
--- a/sdk/lib/_internal/compiler/implementation/lib/js_helper.dart
+++ b/sdk/lib/_internal/compiler/implementation/lib/js_helper.dart
@@ -1016,7 +1016,8 @@ unwrapException(ex) {
     if (message is String) {
       if (message.endsWith('is null') ||
           message.endsWith('is undefined') ||
-          message.endsWith('is null or undefined')) {
+          message.endsWith('is null or undefined') ||
+          message.endsWith('of null')) {
         return new NoSuchMethodError(null, '<unknown>', [], {});
       } else if (contains(message, ' has no method ') ||
                  contains(message, ' is not a function') ||