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

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

 /*
  * 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, 2005, 2006, 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 239 matching lines @@
 {
     if (!m_eventPath) {
         m_eventPath = adoptPtrWillBeNoop(new EventPath(node, this));
     } else {
         m_eventPath->initializeWith(node, this);
     }
 }
 
 WillBeHeapVector<RefPtrWillBeMember<EventTarget>> Event::path(ScriptState* scriptState) const
 {
+    return pathInternal(scriptState, NonEmptyAfterDispatch);
+}
+
+WillBeHeapVector<RefPtrWillBeMember<EventTarget>> Event::deepPath(ScriptState* scriptState) const
+{
+    return pathInternal(scriptState, EmptyAfterDispatch);
+}
+
+WillBeHeapVector<RefPtrWillBeMember<EventTarget>> Event::pathInternal(ScriptState* scriptState, EventPathMode mode) const
+{
     if (m_target)
         OriginsUsingFeatures::countOriginOrIsolatedWorldHumanReadableName(scriptState, *m_target, OriginsUsingFeatures::Feature::EventPath);
 
     if (!m_currentTarget) {
         ASSERT(m_eventPhase == Event::NONE);
         if (!m_eventPath) {
             // Before dispatching the event
             return WillBeHeapVector<RefPtrWillBeMember<EventTarget>>();
         }
         ASSERT(!m_eventPath->isEmpty());
         // After dispatching the event
+        if (mode == EmptyAfterDispatch)
+            return WillBeHeapVector<RefPtrWillBeMember<EventTarget>>();
         return m_eventPath->last().treeScopeEventContext().ensureEventPath(*m_eventPath);
     }
 
     if (Node* node = m_currentTarget->toNode()) {
         ASSERT(m_eventPath);
         size_t eventPathSize = m_eventPath->size();
         for (size_t i = 0; i < eventPathSize; ++i) {
             if (node == (*m_eventPath)[i].node()) {
                 return (*m_eventPath)[i].treeScopeEventContext().ensureEventPath(*m_eventPath);
             }
@@ skipping 46 matching lines @@
 
 DEFINE_TRACE(Event)
 {
     visitor->trace(m_currentTarget);
     visitor->trace(m_target);
     visitor->trace(m_underlyingEvent);
     visitor->trace(m_eventPath);
 }
 
 } // namespace blink