blink: Cleanup class forward declarations

third_party/WebKit/Source/platform/scheduler/base/time_domain.h

 // Copyright 2015 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 THIRD_PARTY_WEBKIT_SOURCE_PLATFORM_SCHEDULER_BASE_TIME_DOMAIN_H_
 #define THIRD_PARTY_WEBKIT_SOURCE_PLATFORM_SCHEDULER_BASE_TIME_DOMAIN_H_
 
 #include <map>
 
 #include "base/callback.h"
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "base/time/time.h"
 #include "platform/scheduler/base/intrusive_heap.h"
 #include "platform/scheduler/base/lazy_now.h"
 #include "platform/scheduler/base/task_queue_impl.h"
 
 namespace blink {
 namespace scheduler {
 namespace internal {
 class TaskQueueImpl;
 }  // internal
 class TaskQueueManager;
-class TaskQueueManagerDelegate;
 
 // The TimeDomain's job is to wake task queues up when their next delayed tasks
 // are due to fire. TaskQueues request a wake up via ScheduleDelayedWork, when
 // the wake up is due the TimeDomain calls TaskQueue::WakeUpForDelayedWork.
 // The TimeDomain communicates with the TaskQueueManager to actually schedule
 // the wake-ups on the underlying base::MessageLoop. Various levels of de-duping
 // are employed to prevent unnecessary posting of TaskQueueManager::DoWork.
 //
 // Note the TimeDomain only knows about the first wakeup per queue, it's the
 // responsibility of TaskQueueImpl to keep the time domain up to date if this
@@ skipping 141 matching lines @@
 
   base::ThreadChecker main_thread_checker_;
 
   DISALLOW_COPY_AND_ASSIGN(TimeDomain);
 };
 
 }  // namespace scheduler
 }  // namespace blink
 
 #endif  // THIRD_PARTY_WEBKIT_SOURCE_PLATFORM_SCHEDULER_BASE_TIME_DOMAIN_H_