Land http://codereview.chromium.org/11047027/ for Matthias:

runtime/vm/object.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_OBJECT_H_
 #define VM_OBJECT_H_
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "platform/utils.h"
@@ skipping 1821 matching lines @@
   static RawLibrary* New(const String& url);
 
   // Library scope name dictionary.
   //
   // TODO(turnidge): The Lookup functions are not consistent in how
   // they deal with private names.  Go through and make them a bit
   // more regular.
   void AddClass(const Class& cls) const;
   void AddObject(const Object& obj, const String& name) const;
   void ReplaceObject(const Object& obj, const String& name) const;
+  RawObject* LookupExport(const String& name) const;
   RawObject* LookupObject(const String& name) const;
   RawClass* LookupClass(const String& name) const;
   RawClass* LookupClassAllowPrivate(const String& name) const;
   RawObject* LookupLocalObject(const String& name) const;
   RawClass* LookupLocalClass(const String& name) const;
   RawField* LookupFieldAllowPrivate(const String& name) const;
   RawField* LookupLocalField(const String& name) const;
   RawFunction* LookupFunctionAllowPrivate(const String& name) const;
   RawFunction* LookupLocalFunction(const String& name) const;
   RawLibraryPrefix* LookupLocalLibraryPrefix(const String& name) const;
   RawScript* LookupScript(const String& url) const;
   RawArray* LoadedScripts() const;
 
   void AddAnonymousClass(const Class& cls) const;
 
+  void AddExport(const Namespace& ns) const;
+
   // Library imports.
   void AddImport(const Namespace& ns) const;
-  RawLibrary* LookupImport(const String& url) const;
   intptr_t num_imports() const { return raw_ptr()->num_imports_; }
   RawNamespace* ImportAt(intptr_t index) const;
   RawLibrary* ImportLibraryAt(intptr_t index) const;
   bool ImportsCorelib() const;
 
   RawFunction* LookupFunctionInSource(const String& script_url,
                                       intptr_t line_number) const;
   RawFunction* LookupFunctionInScript(const Script& script,
                                       intptr_t token_pos) const;
 
@@ skipping 51 matching lines @@
 
  private:
   static const int kInitialImportsCapacity = 4;
   static const int kImportsCapacityIncrement = 8;
   static RawLibrary* New();
 
   void set_num_imports(intptr_t value) const {
     raw_ptr()->num_imports_ = value;
   }
   RawArray* imports() const { return raw_ptr()->imports_; }
+  RawArray* exports() const { return raw_ptr()->exports_; }
+  bool HasExports() const;
   RawArray* loaded_scripts() const { return raw_ptr()->loaded_scripts_; }
   RawArray* dictionary() const { return raw_ptr()->dictionary_; }
   void InitClassDictionary() const;
   void InitImportList() const;
   void GrowDictionary(const Array& dict, intptr_t dict_size) const;
   static RawLibrary* NewLibraryHelper(const String& url,
                                       bool import_core_lib);
   RawObject* LookupEntry(const String& name, intptr_t *index) const;
 
   HEAP_OBJECT_IMPLEMENTATION(Library, Object);
@@ skipping 3785 matching lines @@
     if (this->CharAt(i) != str.CharAt(begin_index + i)) {
       return false;
     }
   }
   return true;
 }
 
 }  // namespace dart
 
 #endif  // VM_OBJECT_H_