Add UseCounters for Event.cancelBubble behavior.

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

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
@@ skipping 16 matching lines @@
 
 #include "core/dom/ContainerNode.h"
 #include "core/dom/Document.h"
 #include "core/dom/Element.h"
 #include "core/events/EventDispatchMediator.h"
 #include "core/events/MouseEvent.h"
 #include "core/events/ScopedEventQueue.h"
 #include "core/events/WindowEventContext.h"
 #include "core/frame/FrameView.h"
 #include "core/frame/LocalDOMWindow.h"
+#include "core/frame/UseCounter.h"
 #include "core/inspector/InspectorTraceEvents.h"
 #include "platform/EventDispatchForbiddenScope.h"
 #include "platform/TraceEvent.h"
 #include "wtf/RefPtr.h"
 
 namespace blink {
 
 DispatchEventResult EventDispatcher::dispatchEvent(Node& node, EventDispatchMediator* mediator)
 {
     TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("blink.debug"), "EventDispatcher::dispatchEvent");
@@ skipping 123 matching lines @@
     m_event->eventPath()[0].handleLocalEvents(*m_event);
     return m_event->propagationStopped() ? DoneDispatching : ContinueDispatching;
 }
 
 inline void EventDispatcher::dispatchEventAtBubbling()
 {
     // Trigger bubbling event handlers, starting at the bottom and working our way up.
     size_t size = m_event->eventPath().size();
     for (size_t i = 1; i < size; ++i) {
         const NodeEventContext& eventContext = m_event->eventPath()[i];
-        if (eventContext.currentTargetSameAsTarget())
+        if (eventContext.currentTargetSameAsTarget()) {
             m_event->setEventPhase(Event::AT_TARGET);
-        else if (m_event->bubbles() && !m_event->cancelBubble())
+        } else if (m_event->bubbles() && !m_event->cancelBubble()) {
             m_event->setEventPhase(Event::BUBBLING_PHASE);
-        else
+        } else {
+            if (m_event->bubbles() && m_event->cancelBubble() && eventContext.node()->hasEventListeners(m_event->type()))
+                UseCounter::count(eventContext.node()->document(), UseCounter::EventCancelBubbleAffected);
             continue;
+        }
         eventContext.handleLocalEvents(*m_event);
         if (m_event->propagationStopped())
             return;
     }
     if (m_event->bubbles() && !m_event->cancelBubble()) {
         m_event->setEventPhase(Event::BUBBLING_PHASE);
         m_event->eventPath().windowEventContext().handleLocalEvents(*m_event);
+    } else if (m_event->bubbles() && m_event->eventPath().windowEventContext().window()->hasEventListeners(m_event->type())) {
+        UseCounter::count(m_event->eventPath().windowEventContext().window()->getExecutionContext(), UseCounter::EventCancelBubbleAffected);
     }
 }
 
 inline void EventDispatcher::dispatchEventPostProcess(EventDispatchHandlingState* preDispatchEventHandlerResult)
 {
     m_event->setTarget(EventPath::eventTargetRespectingTargetRules(*m_node));
     m_event->setCurrentTarget(nullptr);
     m_event->setEventPhase(0);
 
     // Pass the data from the preDispatchEventHandler to the postDispatchEventHandler.
@@ skipping 29 matching lines @@
                 m_event->eventPath()[i].node()->defaultEventHandler(m_event.get());
                 ASSERT(!m_event->defaultPrevented());
                 if (m_event->defaultHandled())
                     return;
             }
         }
     }
 }
 
 } // namespace blink