Add NativeEnqueuer to work with the Enqueuer.

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

Index: sdk/lib/_internal/compiler/implementation/lib/regexp_helper.dart
diff --git a/sdk/lib/_internal/compiler/implementation/lib/regexp_helper.dart b/sdk/lib/_internal/compiler/implementation/lib/regexp_helper.dart
index 42f64939c667c4e28180e546749d0de91dc8d081..7eb22153191408537724edd5dcab899d447934ea 100644
--- a/sdk/lib/_internal/compiler/implementation/lib/regexp_helper.dart
+++ b/sdk/lib/_internal/compiler/implementation/lib/regexp_helper.dart
@@ -23,7 +23,7 @@ regExpGetNative(JSSyntaxRegExp regExp) {
 }
 
 regExpAttachGlobalNative(JSSyntaxRegExp regExp) {
-  JS('var', r'#._re = #', regExp, regExpMakeNative(regExp, global: true));
+  JS('void', r'#._re = #', regExp, regExpMakeNative(regExp, global: true));
 }
 
 regExpMakeNative(JSSyntaxRegExp regExp, {bool global: false}) {
@@ -36,7 +36,7 @@ regExpMakeNative(JSSyntaxRegExp regExp, {bool global: false}) {
   if (ignoreCase) sb.add('i');
   if (global) sb.add('g');
   try {
-    return JS('Object', r'new RegExp(#, #)', pattern, sb.toString());
+    return JS('var', r'new RegExp(#, #)', pattern, sb.toString());
   } catch (e) {
     throw new IllegalJSRegExpException(pattern,
                                        JS('String', r'String(#)', e));