Implement contextmenu attribute with basic support of <menu>

Source/core/events/RelatedEvent.h

Index: Source/core/events/RelatedEvent.h
diff --git a/Source/core/events/RelatedEvent.h b/Source/core/events/RelatedEvent.h
new file mode 100644
index 0000000000000000000000000000000000000000..50dd7b2ae4c8f4a6a41720cb9fe95174450714fd
--- /dev/null
+++ b/Source/core/events/RelatedEvent.h
@@ -0,0 +1,50 @@
+// Copyright 2014 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.
+
+#ifndef RelatedEvent_h
+#define RelatedEvent_h
+
+#include "core/events/Event.h"
+
+namespace WebCore {
+
+struct RelatedEventInit : public EventInit {
+    RelatedEventInit();
+    RefPtr<EventTarget> relatedTarget;
+};
+
+class RelatedEvent FINAL : public Event {
+public:
+    static PassRefPtr<RelatedEvent> create()
+    {
+        return adoptRef(new RelatedEvent);
+    }
+
+    static PassRefPtr<RelatedEvent> create(const AtomicString& eventType);
+    static PassRefPtr<RelatedEvent> create(const AtomicString& eventType, const RelatedEventInit&);
+
+    virtual ~RelatedEvent() { }

[Inactive, 2014/07/16 20:07:25]

nit: should probably be in the cpp.

[pals, 2014/07/17 15:35:46]

Done.

+
+    EventTarget* relatedTarget() const { return m_relatedTarget.get(); }
+    EventTarget* relatedTarget(bool& isNull) const { isNull = !m_relatedTarget; return m_relatedTarget.get(); }

[Inactive, 2014/07/16 20:07:25]

nit: This isNull argument doesn't make much sense for pointers. We should
probably remove the '?' on IDL side.

[pals, 2014/07/17 15:35:47]

Done.

+    void setRelatedTarget(PassRefPtr<EventTarget> relatedTarget) { m_relatedTarget = relatedTarget; }
+
+
+    virtual const AtomicString& interfaceName() const OVERRIDE { return EventNames::RelatedEvent; }
+    virtual bool isRelatedEvent() const OVERRIDE { return true; }
+
+protected:
+    RelatedEvent();
+    RelatedEvent(const AtomicString& type);

[Inactive, 2014/07/16 20:07:25]

nit: explicit

[pals, 2014/07/17 15:35:47]

Done.

+    RelatedEvent(const AtomicString& type, const RelatedEventInit&);
+
+private:
+    RefPtr<EventTarget> m_relatedTarget;
+};
+
+DEFINE_EVENT_TYPE_CASTS(RelatedEvent);
+
+} // namespace WebCore
+
+#endif // RelatedEvent_h