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// 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 ScopedWindowFocusAllowedIndicator_h
#define ScopedWindowFocusAllowedIndicator_h
#include "core/dom/ContextLifecycleObserver.h"
#include "core/dom/ExecutionContext.h"
#include "wtf/Noncopyable.h"
namespace blink {
class ScopedWindowFocusAllowedIndicator final {
WTF_MAKE_NONCOPYABLE(ScopedWindowFocusAllowedIndicator);
public:
explicit ScopedWindowFocusAllowedIndicator(ExecutionContext* executionContext)
: m_observer(adoptPtrWillBeNoop(new Observer(executionContext)))
{
}
~ScopedWindowFocusAllowedIndicator()
{
m_observer->dispose();
}
private:
class Observer final : public NoBaseWillBeGarbageCollectedFinalized<Observer>, public ContextLifecycleObserver {
WILL_BE_USING_GARBAGE_COLLECTED_MIXIN(Observer);
public:
explicit Observer(ExecutionContext* executionContext)
: ContextLifecycleObserver(executionContext)
{
if (executionContext)
executionContext->allowWindowFocus();
}
void dispose()
{
if (executionContext())
executionContext()->consumeWindowFocus();
}
void trace(Visitor* visitor)
{
ContextLifecycleObserver::trace(visitor);
}
};
// In Oilpan, destructors are not allowed to touch other on-heap objects.
// The Observer indirection is needed to keep
// ScopedWindowFocusAllowedIndicator off-heap and thus allows its destructor
// to call executionContext()->consumeWindowFocus().
OwnPtrWillBePersistent<Observer> m_observer;
};
} // namespace blink
#endif // ScopedWindowFocusAllowedIndicator_h
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