Only emit members in mirror helper symbolsmap.

tests/compiler/dart2js/mirror_helper_test.dart

Index: tests/compiler/dart2js/mirror_helper_test.dart
diff --git a/tests/compiler/dart2js/mirror_helper_test.dart b/tests/compiler/dart2js/mirror_helper_test.dart
index cb22b11f79555ec61b5e15e72a5d47d8cfb2859e..ba3b9aff64c5471f08d522f1f92753110f9e5c70 100644
--- a/tests/compiler/dart2js/mirror_helper_test.dart
+++ b/tests/compiler/dart2js/mirror_helper_test.dart
@@ -58,9 +58,8 @@ void testWithMirrorRenaming({bool minify}) {
   Node getNameFunctionNode =
       backend.memberNodes.values.first.first.body.statements.nodes.head;
 
-  Expect.equals(
-      const SourceString(MirrorRenamer.MIRROR_HELPER_GET_NAME_FUNCTION),
-      mirrorRenamer.symbols[renames[getNameFunctionNode.expression.selector]]);
+  Expect.equals(renames[mirrorRenamer.mirrorHelperGetNameFunctionNode.name],
+                renames[getNameFunctionNode.expression.selector]);
   Expect.equals("",
                 renames[getNameFunctionNode.expression.receiver]);
   Expect.equals(1, imports.keys.length);