Support serialization of loadLibrary

pkg/compiler/lib/src/serialization/modelz.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.
 
 /// Implementation of the element model used for deserialiation.
 ///
 /// These classes are created by [ElementDeserializer] triggered by the
 /// [Deserializer].
 
 library dart2js.serialization.modelz;
@@ skipping 440 matching lines @@
   @override
   String get libraryName {
     return _decoder.getString(Key.LIBRARY_NAME);
   }
 
   @override
   bool get exportsHandled => true;
 
   void _ensureExports() {
     if (_exportsMap == null) {
-      _exportsMap = new ListedContainer(_decoder.getElements(Key.EXPORT_SCOPE));
+      _exportsMap = new ListedContainer(
+          _decoder.getElements(Key.EXPORT_SCOPE, isOptional: true));
     }
   }
 
   @override
   void forEachExport(f(Element element)) {
     _ensureExports();
     _exportsMap.forEach(f);
   }
 
   @override
@@ skipping 1778 matching lines @@
   Export get node => _unsupported('node');
 
   String toString() => 'Z$kind($uri)';
 }
 
 class PrefixElementZ extends DeserializedElementZ
     with LibraryMemberMixin
     implements PrefixElement {
   bool _isDeferred;
   ImportElement _deferredImport;
+  GetterElement _loadLibrary;
 
   PrefixElementZ(ObjectDecoder decoder) : super(decoder);
 
   @override
   accept(ElementVisitor visitor, arg) => visitor.visitPrefixElement(this, arg);
 
   void _ensureDeferred() {
     if (_isDeferred == null) {
       _isDeferred = _decoder.getBool(Key.IS_DEFERRED);
-      _deferredImport = _decoder.getElement(Key.IMPORT, isOptional: true);
+      if (_isDeferred) {
+        _deferredImport = _decoder.getElement(Key.IMPORT);
+        _loadLibrary = _decoder.getElement(Key.GETTER);
+      }
     }
   }
 
   @override
   ImportElement get deferredImport {
     _ensureDeferred();
     return _deferredImport;
   }
 
   @override
   bool get isDeferred {
     _ensureDeferred();
     return _isDeferred;
   }
 
   @override
+  GetterElement get loadLibrary {
+    return _loadLibrary;
+  }
+
+  @override
   ElementKind get kind => ElementKind.PREFIX;
 
   @override
   Element lookupLocalMember(String memberName) {
     return _unsupported('lookupLocalMember');
   }
 }
 
 class MetadataAnnotationZ implements MetadataAnnotation {
   final Element annotatedElement;
   final SourceSpan sourcePosition;
   final ConstantExpression constant;
 
   MetadataAnnotationZ(
       this.annotatedElement, this.sourcePosition, this.constant);
 
   @override
   MetadataAnnotation ensureResolved(Resolution resolution) {
     // Do nothing.
   }
 
   @override
   Node get node => throw new UnsupportedError('${this}.node');
 
   @override
   bool get hasNode => false;
 
   String toString() => 'MetadataAnnotationZ(${constant.toDartText()})';
 }