[OriginTrials] Support OriginTrialEnabled IDL attribute on constants

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 150 matching lines @@
     {{exported}}static void preparePrototypeAndInterfaceObject(v8::Local<v8::Context>, const DOMWrapperWorld&, v8::Local<v8::Object> prototypeObject, v8::Local<v8::Function> interfaceObject, v8::Local<v8::FunctionTemplate> interfaceTemplate){% if unscopeables or has_conditional_attributes_on_prototype or conditionally_enabled_methods %};
     {% else %} { }
     {% endif %}
     {% if has_partial_interface %}
     {{exported}}static void updateWrapperTypeInfo(InstallTemplateFunction, PreparePrototypeAndInterfaceObjectFunction);
     {{exported}}static void install{{v8_class}}Template(v8::Isolate*, const DOMWrapperWorld&, v8::Local<v8::FunctionTemplate> interfaceTemplate);
     {% for method in methods if method.overloads and method.overloads.has_partial_overloads %}
     {{exported}}static void register{{method.name | blink_capitalize}}MethodForPartialInterface(void (*)(const v8::FunctionCallbackInfo<v8::Value>&));
     {% endfor %}
     {% endif %}
-    {% for group in attributes|origin_trial_enabled_attributes|groupby('origin_trial_feature_name') %}{{newline}}
-    static void install{{group.grouper}}(ScriptState*, v8::Local<v8::Object> instance);
+    {% for origin_trial_feature_name in origin_trial_feature_names %}{{newline}}
+    static void install{{origin_trial_feature_name}}(ScriptState*, v8::Local<v8::Object> instance);
     {% endfor %}
     {% if has_partial_interface %}
 
 private:
     static InstallTemplateFunction install{{v8_class}}TemplateFunction;
     {% endif %}
 };
 
 {% if has_event_constructor %}
 {{exported}}bool initialize{{cpp_class}}({{cpp_class}}Init&, const Dictionary&, ExceptionState&, const v8::FunctionCallbackInfo<v8::Value>& info);
 
 {% endif %}
 template <>
 struct V8TypeOf<{{cpp_class}}> {
     typedef {{v8_class}} Type;
 };
 
 } // namespace blink
 
 #endif // {{v8_class}}_h