Make customElements.define faster

third_party/WebKit/Source/bindings/core/v8/ScriptCustomElementDefinitionBuilder.cpp

 // Copyright 2016 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.
 
 #include "bindings/core/v8/ScriptCustomElementDefinitionBuilder.h"
 
 #include "bindings/core/v8/DOMWrapperWorld.h"
 #include "bindings/core/v8/ExceptionState.h"
 #include "bindings/core/v8/ScriptCustomElementDefinition.h"
 #include "bindings/core/v8/ScriptState.h"
@@ skipping 68 matching lines @@
     const StringView& name,
     v8::Local<v8::Value>& value) const {
   v8::Isolate* isolate = script_state_->GetIsolate();
   v8::Local<v8::Context> context = script_state_->GetContext();
   v8::Local<v8::String> name_string = V8AtomicString(isolate, name);
   v8::TryCatch try_catch(isolate);
   if (!V8Call(object->Get(context, name_string), value, try_catch)) {
     exception_state_.RethrowV8Exception(try_catch.Exception());
     return false;
   }
-  return true;
+  return script_state_->ContextIsValid();
 }
 
 bool ScriptCustomElementDefinitionBuilder::CheckPrototype() {
   v8::Local<v8::Value> prototype_value;
   if (!ValueForName(constructor_, "prototype", prototype_value))
     return false;
   if (!prototype_value->IsObject()) {
     exception_state_.ThrowTypeError("constructor prototype is not an object");
     return false;
   }
   prototype_ = prototype_value.As<v8::Object>();
   // If retrieving the prototype destroyed the context, indicate that
   // defining the element should not proceed.
-  return true;
+  return script_state_->ContextIsValid();
 }
 
 bool ScriptCustomElementDefinitionBuilder::CallableForName(
     const StringView& name,
     v8::Local<v8::Function>& callback) const {
   v8::Local<v8::Value> value;
   if (!ValueForName(prototype_, name, value))
     return false;
-  // "undefined" means "omitted", so return true.
+  // "undefined" means "omitted" which is valid.
   if (value->IsUndefined())
     return true;
   if (!value->IsFunction()) {
     exception_state_.ThrowTypeError(String::Format(
         "\"%s\" is not a callable object", name.ToString().Ascii().Data()));
     return false;
   }
   callback = value.As<v8::Function>();
   return true;
 }
 
 bool ScriptCustomElementDefinitionBuilder::RetrieveObservedAttributes() {
   v8::Local<v8::Value> observed_attributes_value;
   if (!ValueForName(constructor_, "observedAttributes",
                     observed_attributes_value))
     return false;
   if (observed_attributes_value->IsUndefined())
     return true;
   Vector<AtomicString> list = ToImplSequence<Vector<AtomicString>>(
       script_state_->GetIsolate(), observed_attributes_value, exception_state_);
-  if (exception_state_.HadException())
+  if (exception_state_.HadException() || !script_state_->ContextIsValid())
     return false;
   if (list.IsEmpty())
     return true;
   observed_attributes_.ReserveCapacityForSize(list.size());
   for (const auto& attribute : list)
     observed_attributes_.insert(attribute);
   return true;
 }
 
 bool ScriptCustomElementDefinitionBuilder::RememberOriginalProperties() {
   // Spec requires to use values of these properties at the point
   // CustomElementDefinition is built, even if JS changes them afterwards.
   return CallableForName("connectedCallback", connected_callback_) &&
          CallableForName("disconnectedCallback", disconnected_callback_) &&
          CallableForName("adoptedCallback", adopted_callback_) &&
          CallableForName("attributeChangedCallback",
                          attribute_changed_callback_) &&
          (attribute_changed_callback_.IsEmpty() ||
           RetrieveObservedAttributes());
 }
 
 CustomElementDefinition* ScriptCustomElementDefinitionBuilder::Build(
-    const CustomElementDescriptor& descriptor) {
+    const CustomElementDescriptor& descriptor,
+    CustomElementDefinition::Id id) {
   return ScriptCustomElementDefinition::Create(
-      script_state_.Get(), registry_, descriptor, constructor_,
+      script_state_.Get(), registry_, descriptor, id, constructor_,
       connected_callback_, disconnected_callback_, adopted_callback_,
       attribute_changed_callback_, observed_attributes_);
 }
 
 }  // namespace blink