Refactor Library/CompilationUnit and how we define local Scope.

lib/compiler/implementation/native_handler.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #library('native');
 #import('dart:uri');
 #import('leg.dart');
 #import('elements/elements.dart');
 #import('scanner/scannerlib.dart');
 #import('ssa/ssa.dart');
@@ skipping 21 matching lines @@
       cls.superclass,
       () => <ClassElement>[]);
   directSubtypes.add(cls);
 }
 
 void processNativeClassesInLibrary(Enqueuer world,
                                    CodeEmitterTask emitter,
                                    LibraryElement library) {
   bool hasNativeClass = false;
   final compiler = emitter.compiler;
-  for (Link<Element> link = library.topLevelElements;
+  for (Link<Element> link = library.localMembers;
        !link.isEmpty(); link = link.tail) {
     Element element = link.head;
     if (element.kind == ElementKind.CLASS) {
       ClassElement classElement = element;
       if (classElement.isNative()) {
         hasNativeClass = true;
         world.registerInstantiatedClass(classElement);
         // Also parse the node to know all its methods because
         // otherwise it will only be parsed if there is a call to
         // one of its constructor.
@@ skipping 16 matching lines @@
         const SourceString('defineProperty')));
     world.registerStaticUse(compiler.findHelper(
         const SourceString('toStringForNativeObject')));
   }
 }
 
 void maybeEnableNative(Compiler compiler,
                        LibraryElement library,
                        Uri uri) {
   String libraryName = uri.toString();
-  if (library.script.name.contains('dart/tests/compiler/dart2js_native')
+  if (library.entryCompilationUnit.script.name.contains(
+          'dart/tests/compiler/dart2js_native')
       || libraryName == 'dart:dom_deprecated'
       || libraryName == 'dart:isolate'
       || libraryName == 'dart:html') {
     library.canUseNative = true;
-    library.define(compiler.findHelper(const SourceString('JS')), compiler);
+    library.addToScope(compiler.findHelper(const SourceString('JS')), compiler);
     if (compiler.jsIndexingBehaviorInterface !== null) {
-      library.define(compiler.jsIndexingBehaviorInterface, compiler);
+      library.addToScope(compiler.jsIndexingBehaviorInterface, compiler);
     }
   }
 }
 
 void checkAllowedLibrary(ElementListener listener, Token token) {
   LibraryElement currentLibrary = listener.compilationUnitElement.getLibrary();
   if (!currentLibrary.canUseNative) {
     listener.recoverableError("Unexpected token", token: token);
   }
 }
@@ skipping 232 matching lines @@
                                       String parameters) {
   buffer.add("  if (Object.getPrototypeOf(this).hasOwnProperty");
   buffer.add("('$methodName')) {\n");
   buffer.add("  $code");
   buffer.add("  } else {\n");
   buffer.add("    return Object.prototype.$methodName.call(this");
   buffer.add(parameters == '' ? '' : ', $parameters');
   buffer.add(");\n");
   buffer.add("  }\n");
 }