Make it possible to inherit from any constructable host object

sky/engine/tonic/dart_wrappable.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef SKY_ENGINE_TONIC_DART_WRAPPABLE_H_
 #define SKY_ENGINE_TONIC_DART_WRAPPABLE_H_
 
 #include "base/logging.h"
 #include "base/template_util.h"
 #include "dart/runtime/include/dart_api.h"
@@ skipping 22 matching lines @@
   // and provide information about their wrapper. There is no need to call your
   // base class's implementation of this function.
   virtual const DartWrapperInfo& GetDartWrapperInfo() const = 0;
 
   // Subclasses that wish to integrate with the Dart garbage collector should
   // override this function. Please call your base class's AcceptDartGCVisitor
   // at the end of your override.
   virtual void AcceptDartGCVisitor(DartGCVisitor& visitor) const;
 
   Dart_Handle CreateDartWrapper(DartState* dart_state);
+  void AssociateWithDartWrapper(Dart_NativeArguments args);
   Dart_WeakPersistentHandle dart_wrapper() const { return dart_wrapper_; }
 
  protected:
   virtual ~DartWrappable();
 
  private:
   static void FinalizeDartWrapper(void* isolate_callback_data,
                                   Dart_WeakPersistentHandle wrapper,
                                   void* peer);
 
@@ skipping 73 matching lines @@
   static Dart_Handle ToDart(RefPtr<T> val) {
     return DartConverter<T*>::ToDart(val.get());
   }
 
   static RefPtr<T> FromDart(Dart_Handle handle) {
     return DartConverter<T*>::FromDart(handle);
   }
 };
 
 template<typename T>
-static T* GetReceiver(Dart_NativeArguments args) {
+inline T* GetReceiver(Dart_NativeArguments args) {
   intptr_t receiver;
   Dart_Handle result = Dart_GetNativeReceiver(args, &receiver);
   DCHECK(!Dart_IsError(result));
   return static_cast<T*>(reinterpret_cast<DartWrappable*>(receiver));
 }
 
 }  // namespace blink
 
 #endif  // SKY_ENGINE_TONIC_DART_WRAPPABLE_H_