Clone of chromium aad1ce808763f59c7a3753e08f1500a104ecc6fd refs/remotes/origin/HEAD
diff --git a/cc/base/unique_notifier.h b/cc/base/unique_notifier.h
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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 CC_BASE_UNIQUE_NOTIFIER_H_
+#define CC_BASE_UNIQUE_NOTIFIER_H_
+
+#include "base/callback.h"
+#include "base/memory/weak_ptr.h"
+#include "cc/base/cc_export.h"
+
+namespace base {
+class SequencedTaskRunner;
+} // namespace base
+
+namespace cc {
+
+class CC_EXPORT UniqueNotifier {
+ public:
+ // Configure this notifier to issue the |closure| notification when scheduled.
+ UniqueNotifier(base::SequencedTaskRunner* task_runner,
+ const base::Closure& closure);
+
+ // Destroying the notifier will ensure that no further notifications will
+ // happen from this class.
+ ~UniqueNotifier();
+
+ // Schedule a notification to be run. If another notification is already
+ // pending, then only one notification will take place.
+ void Schedule();
+
+ private:
+ void Notify();
+
+ // TODO(dcheng): How come this doesn't need to hold a ref to the task runner?
+ base::SequencedTaskRunner* task_runner_;
+ base::Closure closure_;
+ bool notification_pending_;
+
+ base::WeakPtrFactory<UniqueNotifier> weak_ptr_factory_;
+};
+
+} // namespace cc
+
+#endif // CC_BASE_UNIQUE_NOTIFIER_H_
