Add NativeClassData/NativeClassDataBuilder

pkg/compiler/lib/src/js_backend/frequency_namer.dart

Index: pkg/compiler/lib/src/js_backend/frequency_namer.dart
diff --git a/pkg/compiler/lib/src/js_backend/frequency_namer.dart b/pkg/compiler/lib/src/js_backend/frequency_namer.dart
index 49aecfef9a41fe62289d38ef6c1bc9e3bc2c578e..651c99f1f00c8767d2abe044e2dee1214744b0ee 100644
--- a/pkg/compiler/lib/src/js_backend/frequency_namer.dart
+++ b/pkg/compiler/lib/src/js_backend/frequency_namer.dart
@@ -25,9 +25,9 @@ class FrequencyBasedNamer extends Namer
   jsAst.Name get staticsPropertyName =>
       _staticsPropertyName ??= getFreshName(instanceScope, 'static');
 
-  FrequencyBasedNamer(JavaScriptBackend backend, ClosedWorld closedWorld,
-      CodegenWorldBuilder codegenWorldBuilder)
-      : super(backend, closedWorld, codegenWorldBuilder) {
+  FrequencyBasedNamer(BackendHelpers helpers, NativeData nativeData,
+      ClosedWorld closedWorld, CodegenWorldBuilder codegenWorldBuilder)
+      : super(helpers, nativeData, closedWorld, codegenWorldBuilder) {
     fieldRegistry = new _FieldNamingRegistry(this);
   }