[Bindings] Code cleanup: Early return if funtime enabled interface is false

third_party/WebKit/Source/bindings/templates/interface_base.cpp.tmpl

Index: third_party/WebKit/Source/bindings/templates/interface_base.cpp.tmpl
diff --git a/third_party/WebKit/Source/bindings/templates/interface_base.cpp.tmpl b/third_party/WebKit/Source/bindings/templates/interface_base.cpp.tmpl
index 4f5907cb56c3deb03322d19f113e300e502cb469..bbea073618ebe5992dc19695ea8723754ac795bd 100644
--- a/third_party/WebKit/Source/bindings/templates/interface_base.cpp.tmpl
+++ b/third_party/WebKit/Source/bindings/templates/interface_base.cpp.tmpl
@@ -405,6 +405,13 @@ static void install{{v8_class}}Template(v8::Isolate* isolate, const DOMWrapperWo
   interfaceTemplate->SetLength({{interface_length}});
   {% endif %}
   {% endif %}{# is_partial #}
+
+  {% if runtime_enabled_feature_name %}
+  if (!{{runtime_enabled_feature_name | runtime_enabled_function}}) {

[Yuki, 2017/01/13 02:38:37]

This is okay, but I guess you should be able to write:
  if (!{{is_runtime_enabled(runtime_enabled_feature_name)}}) {
  }
They're equivalent, though.

[Yuki, 2017/01/13 02:38:37]

If the feature is disabled, we shouldn't hit this line.  Do you have any clues
why we're calling V8Type::installTypeTemplate() even when Type is disabled?  Who
is calling the function?

[peria, 2017/01/13 05:54:26]

V8Type::domTemplate() calls it through V8DOMConfiguration::domClassTemplate(),
and domTemplate()'s caller is handler of V8Type::wrapperTypeInfo.

So if we want to avoid calling V8Type::installV8TypeTemplate()
depending on runtime enabled flags, we need to make a branch in
V8Type::domTemplate().

[peria, 2017/01/13 05:54:26]

As a context of Jinja, I think it better to make the content of
|runtime_enabled_feature_name| (e.g. "FooBar") to be the function name (e.g.
"RuntimeEnabledFeatures::fooBarEnabled()").

+    return;
+  }
+  {% endif %}
+
   v8::Local<v8::Signature> signature = v8::Signature::New(isolate, interfaceTemplate);
   ALLOW_UNUSED_LOCAL(signature);
   v8::Local<v8::ObjectTemplate> instanceTemplate = interfaceTemplate->InstanceTemplate();
@@ -427,7 +434,6 @@ static void install{{v8_class}}Template(v8::Isolate* isolate, const DOMWrapperWo
   {% endif %}
 
   // Register DOM constants, attributes and operations.
-  {% filter runtime_enabled(runtime_enabled_feature_name) %}
   {% if constants %}
   {{install_constants() | indent(2)}}
   {% endif %}
@@ -443,7 +449,6 @@ static void install{{v8_class}}Template(v8::Isolate* isolate, const DOMWrapperWo
   {% if methods | has_method_configuration(is_partial) %}
   V8DOMConfiguration::installMethods(isolate, world, instanceTemplate, prototypeTemplate, interfaceTemplate, signature, {{'%sMethods' % v8_class}}, {{'WTF_ARRAY_LENGTH(%sMethods)' % v8_class}});
   {% endif %}
-  {% endfilter %}
 
   {% if has_access_check_callbacks and not is_partial %}
   // Cross-origin access check
@@ -454,9 +459,9 @@ static void install{{v8_class}}Template(v8::Isolate* isolate, const DOMWrapperWo
   instanceTemplate->SetAccessCheckCallbackAndHandler({{cpp_class}}V8Internal::securityCheck, v8::NamedPropertyHandlerConfiguration({{cross_origin_named_getter}}, {{cross_origin_named_setter}}, nullptr, nullptr, {{cross_origin_named_enumerator}}), v8::IndexedPropertyHandlerConfiguration({{cross_origin_indexed_getter}}), v8::External::New(isolate, const_cast<WrapperTypeInfo*>(&{{v8_class}}::wrapperTypeInfo)));
   {% endif %}
 
-  {% for group in runtime_enabled_attributes | groupby('runtime_enabled_feature_name') %}
-  {% filter runtime_enabled(group.list[0].runtime_enabled_feature_name) %}
-  {% for attribute in group.list | unique_by('name') | sort %}
+  {% for feature_name, attribute_list in runtime_enabled_attributes | groupby('runtime_enabled_feature_name') %}
+  {% filter runtime_enabled(feature_name) %}
+  {% for attribute in attribute_list | unique_by('name') | sort %}
   {% if attribute.is_data_type_property %}
   const V8DOMConfiguration::AttributeConfiguration attribute{{attribute.name}}Configuration = {{attribute_configuration(attribute)}};
   V8DOMConfiguration::installAttribute(isolate, world, instanceTemplate, prototypeTemplate, attribute{{attribute.name}}Configuration);