Remove parts of //cc we aren't using

cc/base/delayed_unique_notifier.h

-// 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_DELAYED_UNIQUE_NOTIFIER_H_
-#define CC_BASE_DELAYED_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 DelayedUniqueNotifier {
- public:
-  // Configure this notifier to issue the |closure| notification in |delay| time
-  // from Schedule() call.
-  DelayedUniqueNotifier(base::SequencedTaskRunner* task_runner,
-                        const base::Closure& closure,
-                        const base::TimeDelta& delay);
-
-  // Destroying the notifier will ensure that no further notifications will
-  // happen from this class.
-  virtual ~DelayedUniqueNotifier();
-
-  // Schedule a notification to be run. If another notification is already
-  // pending, then it will happen in (at least) given delay from now. That is,
-  // if delay is 16ms and a notification has been scheduled 10ms ago (ie, it
-  // should trigger in no less than 6ms), then calling schedule will ensure that
-  // the only notification that arrives will happen in (at least) 16ms from now.
-  void Schedule();
-
-  // Cancel any previously scheduled runs.
-  void Cancel();
-
-  // Cancel previously scheduled runs and prevent any new runs from starting.
-  // After calling this the DelayedUniqueNotifier will have no outstanding
-  // WeakPtrs.
-  void Shutdown();
-
-  // Returns true if a notification is currently scheduled to run.
-  bool HasPendingNotification() const;
-
- protected:
-  // Virtual for testing.
-  virtual base::TimeTicks Now() const;
-
- private:
-  void NotifyIfTime();
-
-  base::SequencedTaskRunner* task_runner_;
-  base::Closure closure_;
-  base::TimeDelta delay_;
-  base::TimeTicks next_notification_time_;
-  bool notification_pending_;
-
-  base::WeakPtrFactory<DelayedUniqueNotifier> weak_ptr_factory_;
-
-  DISALLOW_COPY_AND_ASSIGN(DelayedUniqueNotifier);
-};
-
-}  // namespace cc
-
-#endif  // CC_BASE_DELAYED_UNIQUE_NOTIFIER_H_