First implementation of lazily cached accessor for DOM attributes.

third_party/WebKit/Source/platform/bindings/V8PrivateProperty.h

Index: third_party/WebKit/Source/platform/bindings/V8PrivateProperty.h
diff --git a/third_party/WebKit/Source/platform/bindings/V8PrivateProperty.h b/third_party/WebKit/Source/platform/bindings/V8PrivateProperty.h
index 561e0aedfdc945b20b0ed7ee1569c8aca85dacdf..442f19ce5ef98f43fc71e75abcba9b26d40bac96 100644
--- a/third_party/WebKit/Source/platform/bindings/V8PrivateProperty.h
+++ b/third_party/WebKit/Source/platform/bindings/V8PrivateProperty.h
@@ -39,9 +39,12 @@ class ScriptWrappable;
   X(CustomElementLifecycle, CreatedCallback)          \
   X(CustomElementLifecycle, DetachedCallback)         \
   X(DOMException, Error)                              \
+  X(Element, IdCachedAccessor)                        \
   X(ErrorEvent, Error)                                \
   X(FetchEvent, Request)                              \
   X(Global, Event)                                    \
+  X(HTMLElement, TitleCachedAccessor)                 \
+  X(HTMLElement, LangCachedAccessor)                  \
   X(IDBCursor, Request)                               \
   X(IDBObserver, Callback)                            \
   X(InternalBody, Buffer)                             \