Add NativeDataResolver

pkg/compiler/lib/src/world.dart

Index: pkg/compiler/lib/src/world.dart
diff --git a/pkg/compiler/lib/src/world.dart b/pkg/compiler/lib/src/world.dart
index 4ea2abc7932387a412cd27815019f64a1e3f4047..46051dcef6d2e82e9de3a4b63252fd1b166647b0 100644
--- a/pkg/compiler/lib/src/world.dart
+++ b/pkg/compiler/lib/src/world.dart
@@ -22,7 +22,7 @@ import 'elements/elements.dart'
 import 'elements/resolution_types.dart';
 import 'js_backend/backend.dart' show JavaScriptBackend;
 import 'js_backend/interceptor_data.dart' show InterceptorData;
-import 'js_backend/native_data.dart' show NativeClassData;
+import 'js_backend/native_data.dart' show NativeData;
 import 'ordered_typeset.dart';
 import 'types/masks.dart' show CommonMasks, FlatTypeMask, TypeMask;
 import 'universe/class_set.dart';
@@ -47,6 +47,8 @@ abstract class ClosedWorld implements World {
   /// Access to core classes used by the backend.
   BackendClasses get backendClasses;
 
+  NativeData get nativeData;
+
   InterceptorData get interceptorData;
 
   CommonElements get commonElements;
@@ -446,7 +448,7 @@ class ClosedWorldImpl implements ClosedWorld, ClosedWorldRefiner {
     _allFunctions = functionSetBuilder.close(this);
   }
 
-  NativeClassData get _nativeClassData => _backend.nativeClassData;
+  NativeData get nativeData => _backend.nativeData;
 
   @override
   ClosedWorld get closedWorld => this;
@@ -714,7 +716,7 @@ class ClosedWorldImpl implements ClosedWorld, ClosedWorldRefiner {
   @override
   ClassElement getLubOfInstantiatedSubclasses(ClassElement cls) {
     assert(isClosed);
-    if (_nativeClassData.isJsInteropClass(cls)) {
+    if (nativeData.isJsInteropClass(cls)) {
       return _backend.helpers.jsJavaScriptObjectClass;
     }
     ClassHierarchyNode hierarchy = _classHierarchyNodes[cls.declaration];
@@ -726,7 +728,7 @@ class ClosedWorldImpl implements ClosedWorld, ClosedWorldRefiner {
   @override
   ClassElement getLubOfInstantiatedSubtypes(ClassElement cls) {
     assert(isClosed);
-    if (_nativeClassData.isJsInteropClass(cls)) {
+    if (nativeData.isJsInteropClass(cls)) {
       return _backend.helpers.jsJavaScriptObjectClass;
     }
     ClassSet classSet = _classSets[cls.declaration];
@@ -1096,7 +1098,7 @@ class ClosedWorldImpl implements ClosedWorld, ClosedWorldRefiner {
 
   bool fieldNeverChanges(MemberElement element) {
     if (!element.isField) return false;
-    if (_nativeClassData.isNativeMember(element)) {
+    if (nativeData.isNativeMember(element)) {
       // Some native fields are views of data that may be changed by operations.
       // E.g. node.firstChild depends on parentNode.removeBefore(n1, n2).
       // TODO(sra): Refine the effect classification so that native effects are