Add "Failed" custom element state

third_party/WebKit/Source/core/dom/custom/CustomElementDefinition.cpp

Index: third_party/WebKit/Source/core/dom/custom/CustomElementDefinition.cpp
diff --git a/third_party/WebKit/Source/core/dom/custom/CustomElementDefinition.cpp b/third_party/WebKit/Source/core/dom/custom/CustomElementDefinition.cpp
index b5666d53ed97670c8d1a7ee19172d42d9e5f42c1..c4591086df199461c723131c2f40444eaf0ac08f 100644
--- a/third_party/WebKit/Source/core/dom/custom/CustomElementDefinition.cpp
+++ b/third_party/WebKit/Source/core/dom/custom/CustomElementDefinition.cpp
@@ -122,8 +122,10 @@ void CustomElementDefinition::upgrade(Element* 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);
 }