Implement contextmenu attribute with basic support of <menu>

Source/core/events/RelatedEvent.h

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

[esprehn, 2014/06/06 22:30:42]

I don't know what this method is, but you definitely don't need it. Just check
relatedTarget() in callers.

[pals, 2014/06/10 10:42:39]

It is being called by generated files
gen/blink/bindings/core/v8/V8RelatedEvent.cpp:53:66: error: no matching function
for call to ‘WebCore::RelatedEvent::relatedTarget(bool&)’

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

[esprehn, 2014/06/06 22:30:41]

Shouldn't this be virtual?

[pals, 2014/06/10 10:42:39]

Done.

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