Make Event.deepPath() return an empty array if an event is no longer being dispatched

third_party/WebKit/Source/core/events/Event.h

 /*
  * Copyright (C) 2001 Peter Kelly (pmk@post.com)
  * Copyright (C) 2001 Tobias Anton (anton@stud.fbi.fh-darmstadt.de)
  * Copyright (C) 2006 Samuel Weinig (sam.weinig@gmail.com)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
@@ skipping 169 matching lines @@
     bool cancelBubble() const { return m_cancelBubble; }
     void setCancelBubble(bool cancel) { m_cancelBubble = cancel; }
 
     Event* underlyingEvent() const { return m_underlyingEvent.get(); }
     void setUnderlyingEvent(PassRefPtrWillBeRawPtr<Event>);
 
     EventPath& eventPath() { ASSERT(m_eventPath); return *m_eventPath; }
     void initEventPath(Node&);
 
     WillBeHeapVector<RefPtrWillBeMember<EventTarget>> path(ScriptState*) const;
+    WillBeHeapVector<RefPtrWillBeMember<EventTarget>> deepPath(ScriptState*) const;
 
     bool isBeingDispatched() const { return eventPhase(); }
 
     // Events that must not leak across isolated world, similar to how
     // ErrorEvent behaves, can override this method.
     virtual bool canBeDispatchedInWorld(const DOMWrapperWorld&) const { return true; }
 
     virtual PassRefPtrWillBeRawPtr<EventDispatchMediator> createMediator();
 
     bool isTrusted() const { return m_isTrusted; }
@@ skipping 10 matching lines @@
     Event(const AtomicString& type, bool canBubble, bool cancelable, bool scoped);
     Event(const AtomicString& type, bool canBubble, bool cancelable, bool scoped, double platformTimeStamp);
     Event(const AtomicString& type, const EventInit&);
 
     virtual void receivedTarget();
     bool dispatched() const { return m_target; }
 
     void setCanBubble(bool bubble) { m_canBubble = bubble; }
 
 private:
+    enum EventPathMode {
+        EmptyAfterDispatch,
+        NonEmptyAfterDispatch
+    };
+
     AtomicString m_type;
     unsigned m_canBubble:1;
     unsigned m_cancelable:1;
     unsigned m_scoped:1;
 
     unsigned m_propagationStopped:1;
     unsigned m_immediatePropagationStopped:1;
     unsigned m_defaultPrevented:1;
     unsigned m_defaultHandled:1;
     unsigned m_cancelBubble:1;
     unsigned m_isTrusted : 1;
     unsigned m_handlingPassive : 1;
 
     unsigned short m_eventPhase;
     RefPtrWillBeMember<EventTarget> m_currentTarget;
     RefPtrWillBeMember<EventTarget> m_target;
     DOMTimeStamp m_createTime;
     RefPtrWillBeMember<Event> m_underlyingEvent;
     OwnPtrWillBeMember<EventPath> m_eventPath;
     // The monotonic platform time in seconds, for input events it is the
     // event timestamp provided by the host OS and reported in the original
     // WebInputEvent instance.
     double m_platformTimeStamp;
+
+    WillBeHeapVector<RefPtrWillBeMember<EventTarget>> pathInternal(ScriptState*, EventPathMode) const;

[kochi, 2016/02/25 09:49:40]

nit: usually method declaration comes after enum and before data members?

It may not be mandatory for blink style, though:
https://www.chromium.org/blink/coding-style

[hayato, 2016/02/25 10:22:55]

Done.

 };
 
 #define DEFINE_EVENT_TYPE_CASTS(typeName) \
     DEFINE_TYPE_CASTS(typeName, Event, event, event->is##typeName(), event.is##typeName())
 
 } // namespace blink
 
 #endif // Event_h