isLoaded can now handle elements from other libraries

lib/src/codegen/js_module_item_order.dart

 // Copyright (c) 2015, 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.
 
 import 'dart:collection' show HashMap;
 import 'package:analyzer/src/generated/ast.dart';
 import 'package:analyzer/src/generated/element.dart';
 import 'package:dev_compiler/src/dependency_graph.dart' show corelibOrder;
 
 typedef void ModuleItemEmitter(AstNode item);
@@ skipping 28 matching lines @@
 
   /// Memoized results of [_inLibraryCycle].
   final _libraryCycleMemo = new HashMap<LibraryElement, bool>();
 
   final ModuleItemEmitter _emitModuleItem;
 
   LibraryElement _currentLibrary;
 
   ModuleItemLoadOrder(this._emitModuleItem);
 
-  bool isLoaded(Element e) => _loaded[e] == true;
+  bool isLoaded(Element e) => (e.library == _currentLibrary)
+      ? _loaded[e] == true
+      : libraryIsLoaded(e.library);
 
   /// Collect top-level elements and nodes we need to emit.
   void collectElements(
       LibraryElement library, Iterable<CompilationUnit> partsThenLibrary) {
     assert(_currentLibrary == null);
     _currentLibrary = library;
 
     for (var unit in partsThenLibrary) {
       for (var decl in unit.declarations) {
         _declarationNodes[decl.element] = decl;
@@ skipping 158 matching lines @@
       if (result) break;
       result = _inLibraryCycle(e.importedLibrary);
     }
     for (var e in library.exports) {
       if (result) break;
       result = _inLibraryCycle(e.exportedLibrary);
     }
     return _libraryCycleMemo[library] = result;
   }
 }