third_party/WebKit/Source/core/dom/custom/V0CustomElementObserver.cpp

/*
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 *    in the documentation and/or other materials provided with the
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 *    may be used to endorse or promote products derived from this
 *    software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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#include "core/dom/custom/V0CustomElementObserver.h"

#include "core/dom/Element.h"

namespace blink {

// Maps elements to the observer watching them. At most one per
// element at a time.
typedef HeapHashMap<WeakMember<Element>, Member<V0CustomElementObserver>> ElementObserverMap;

static ElementObserverMap& elementObservers()
{
    DEFINE_STATIC_LOCAL(ElementObserverMap, map, (new ElementObserverMap));
    return map;
}

void V0CustomElementObserver::notifyElementWasDestroyed(Element* element)
{
    ElementObserverMap::iterator it = elementObservers().find(element);
    if (it == elementObservers().end())
        return;
    it->value->elementWasDestroyed(element);
}

void V0CustomElementObserver::observe(Element* element)
{
    ElementObserverMap::AddResult result = elementObservers().add(element, this);
    ASSERT_UNUSED(result, result.isNewEntry);
}

void V0CustomElementObserver::unobserve(Element* element)
{
    V0CustomElementObserver* observer = elementObservers().take(element);
    ASSERT_UNUSED(observer, observer == this);
}

} // namespace blink