Implement contextmenu attribute with basic support of <menu>

Source/core/html/HTMLElement.h

Index: Source/core/html/HTMLElement.h
diff --git a/Source/core/html/HTMLElement.h b/Source/core/html/HTMLElement.h
index 717a6085c2fa05e974f52bd1dff584fccb2440fc..65da13daad43e4db86aa1cc10b3e5b80067a6af2 100644
--- a/Source/core/html/HTMLElement.h
+++ b/Source/core/html/HTMLElement.h
@@ -30,6 +30,7 @@ namespace blink {
 class DocumentFragment;
 class HTMLCollection;
 class HTMLFormElement;
+class HTMLMenuElement;
 class ExceptionState;
 
 enum TranslateAttributeMode {
@@ -95,6 +96,9 @@ public:
 
     static const AtomicString& eventParameterName();
 
+    PassRefPtrWillBeRawPtr<HTMLMenuElement> contextMenu() const;

[tkent, 2014/07/31 06:07:55]

The return value should be HTMLMenuElement* because this function should not
move ownership.

[pals, 2014/08/01 10:03:07]

Done.

+    void setContextMenu(PassRefPtrWillBeRawPtr<HTMLMenuElement>);

[tkent, 2014/07/31 06:07:55]

The argument type should be HTMLMenuElement*.

[pals, 2014/08/01 10:03:07]

Done.

+
 protected:
     HTMLElement(const QualifiedName& tagName, Document&, ConstructionType);