[WIP] bindings: Introduce PropertyBag

Source/bindings/templates/interface.h

 // Copyright 2014 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.
 
 // This file has been auto-generated by {{code_generator}}. DO NOT MODIFY!
 
 #ifndef {{v8_class}}_h
 #define {{v8_class}}_h
 
 {% filter conditional(conditional_string) %}
 {% for filename in header_includes %}
 #include "{{filename}}"
 {% endfor %}
 
 namespace blink {
 
 {% if has_event_constructor %}
-class Dictionary;
+class PropertyBag;
 {% endif %}
 {% if named_constructor %}
 class {{v8_class}}Constructor {
 public:
     static v8::Handle<v8::FunctionTemplate> domTemplate(v8::Isolate*);
     static const WrapperTypeInfo wrapperTypeInfo;
 };
 
 {% endif %}
 class {{v8_class}} {
@@ skipping 250 matching lines @@
     v8SetReturnValueForMainWorld(callbackInfo, impl.get());
 }
 
 template<class CallbackInfo, class Wrappable>
 inline void v8SetReturnValueFast(const CallbackInfo& callbackInfo, {{pass_cpp_type}} impl, Wrappable* wrappable)
 {
     v8SetReturnValueFast(callbackInfo, impl.get(), wrappable);
 }
 
 {% if has_event_constructor %}
-bool initialize{{cpp_class}}({{cpp_class}}Init&, const Dictionary&, ExceptionState&, const v8::FunctionCallbackInfo<v8::Value>& info, const String& = "");
+bool initialize{{cpp_class}}({{cpp_class}}Init&, const PropertyBag&, ExceptionState&, const v8::FunctionCallbackInfo<v8::Value>& info, const String& = "");
 
 {% endif %}
+template <>
+struct PropertyBagTraits<{{cpp_class}}> {
+    typedef {{v8_class}} type;
+};
+
 } // namespace blink
 {% endfilter %}
 #endif // {{v8_class}}_h