Have bindings layer assume and insist that all interface types are GCed.

third_party/WebKit/Source/bindings/templates/interface.h

 {% include 'copyright_block.txt' %}
 #ifndef {{v8_class}}_h
 #define {{v8_class}}_h
 
 {% for filename in header_includes %}
 #include "{{filename}}"
 {% endfor %}
 
 namespace blink {
 
@@ skipping 41 matching lines @@
     {
         return toScriptWrappable(object)->toImpl<{{cpp_class}}>();
     }
     {% endif %}
     {{exported}}static {{cpp_class}}* toImplWithTypeCheck(v8::Isolate*, v8::Local<v8::Value>);
     {% if has_partial_interface %}
     {{exported}}static WrapperTypeInfo wrapperTypeInfo;
     {% else %}
     {{exported}}static const WrapperTypeInfo wrapperTypeInfo;
     {% endif %}
-    static void refObject(ScriptWrappable*);
-    static void derefObject(ScriptWrappable*);
     template<typename VisitorDispatcher>
     static void trace(VisitorDispatcher visitor, ScriptWrappable* scriptWrappable)
     {
-        {% if gc_type == 'GarbageCollectedObject' %}
         visitor->trace(scriptWrappable->toImpl<{{cpp_class}}>());
-        {% endif %}
     }
     {% if has_visit_dom_wrapper %}
     static void visitDOMWrapper(v8::Isolate*, ScriptWrappable*, const v8::Persistent<v8::Object>&);
     {% endif %}
     {% if active_scriptwrappable %}
     static ActiveScriptWrappable* toActiveScriptWrappable(v8::Local<v8::Object>);
     {% endif %}
     {% for method in methods %}
     {% if method.is_custom %}
     static void {{method.name}}MethodCustom(const v8::FunctionCallbackInfo<v8::Value>&);
@@ skipping 100 matching lines @@
 
 {% endif %}
 template <>
 struct V8TypeOf<{{cpp_class}}> {
     typedef {{v8_class}} Type;
 };
 
 } // namespace blink
 
 #endif // {{v8_class}}_h