Delay Class parsing until the class is actually used.

runtime/vm/class_finalizer.h

 // 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.
 
 #ifndef VM_CLASS_FINALIZER_H_
 #define VM_CLASS_FINALIZER_H_
 
 #include "vm/allocation.h"
 #include "vm/growable_array.h"
 
@@ skipping 65 matching lines @@
 
   // Return false if we still have classes pending to be finalized.
   static bool AllClassesFinalized();
 
   // Return whether class finalization failed.
   // The function returns true if the finalization was successful.
   // If finalization fails, an error message is set in the sticky error field
   // in the object store.
   static bool FinalizePendingClasses();
 
+  static void FinalizeTypesInClass(const Class& cls);
+
+  static void FinalizeClass(const Class& cls);
 
   // Verify that the classes have been properly prefinalized. This is
   // needed during bootstrapping where the classes have been preloaded.
   static void VerifyBootstrapClasses();
 
  private:
-  static void FinalizeClass(const Class& cls);
   static bool IsSuperCycleFree(const Class& cls);
   static bool IsAliasCycleFree(const Class& cls,
                                GrowableArray<intptr_t>* visited);
   static void CheckForLegalConstClass(const Class& cls);
   static RawClass* ResolveClass(const Class& cls,
                                 const UnresolvedClass& unresolved_class);
   static void ResolveRedirectingFactoryTarget(
       const Class& cls,
       const Function& factory,
       const GrowableObjectArray& visited_factories);
   static void CloneTypeParameters(const Class& mixapp_class);
+  static void ApplyMixinTypes(const Class& cls);
   static void ApplyMixin(const Class& cls);
   static void CollectTypeArguments(const Class& cls,
                                    const Type& type,
                                    const GrowableObjectArray& collected_args);
   static RawType* ResolveMixinAppType(const Class& cls,
                                       const MixinAppType& mixin_app);
   static void ResolveSuperTypeAndInterfaces(const Class& cls,
                                             GrowableArray<intptr_t>* visited);
   static void FinalizeTypeParameters(const Class& cls);
   static void FinalizeTypeArguments(const Class& cls,
@@ skipping 27 matching lines @@
   static void ReportError(const char* format, ...) PRINTF_ATTRIBUTE(1, 2);
 
   // Verify implicit offsets recorded in the VM for direct access to fields of
   // Dart instances (e.g: _TypedListView, _ByteDataView).
   static void VerifyImplicitFieldOffsets();
 };
 
 }  // namespace dart
 
 #endif  // VM_CLASS_FINALIZER_H_