Add "Failed" custom element state

third_party/WebKit/Source/core/dom/custom/CustomElementDefinition.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 "core/dom/custom/CustomElementDefinition.h"
 
 #include "core/dom/Attr.h"
 #include "core/dom/ExceptionCode.h"
 #include "core/dom/custom/CustomElement.h"
 #include "core/dom/custom/CustomElementAttributeChangedCallbackReaction.h"
@@ skipping 102 matching lines @@
     size_t depth = m_constructionStack.size();
 
     bool succeeded = runConstructor(element);
 
     // Pop the construction stack.
     if (m_constructionStack.last().get())
         DCHECK_EQ(m_constructionStack.last(), element);
     DCHECK_EQ(m_constructionStack.size(), depth); // It's a *stack*.
     m_constructionStack.removeLast();
 
-    if (!succeeded)
+    if (!succeeded) {
+        element->setCustomElementState(CustomElementState::Failed);
         return;
+    }
 
     CHECK(element->getCustomElementState() == CustomElementState::Custom);
 }
 
 bool CustomElementDefinition::hasAttributeChangedCallback(
     const QualifiedName& name)
 {
     return m_observedAttributes.contains(name.localName());
 }
 
@@ skipping 34 matching lines @@
         element->synchronizeAttribute(name);
     for (const auto& attribute : element->attributesWithoutUpdate()) {
         if (hasAttributeChangedCallback(attribute.name())) {
             enqueueAttributeChangedCallback(element, attribute.name(),
                 nullAtom, attribute.value());
         }
     }
 }
 
 } // namespace blink