blink: Cleanup class forward declarations

third_party/WebKit/Source/platform/scheduler/renderer/task_queue_throttler.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_RENDERER_THROTTLING_HELPER_H_
 #define THIRD_PARTY_WEBKIT_SOURCE_PLATFORM_SCHEDULER_RENDERER_THROTTLING_HELPER_H_
 
 #include <set>
 #include <unordered_map>
 
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/optional.h"
 #include "base/threading/thread_checker.h"
 #include "platform/scheduler/base/cancelable_closure_holder.h"
 #include "platform/scheduler/base/time_domain.h"
 #include "public/platform/WebViewScheduler.h"
 
 namespace blink {
 namespace scheduler {
 
 class RendererSchedulerImpl;
 class ThrottledTimeDomain;
-class WebFrameSchedulerImpl;
 
 // The job of the TaskQueueThrottler is to control when tasks posted on
 // throttled queues get run. The TaskQueueThrottler:
 // - runs throttled tasks once per second,
 // - controls time budget for task queues grouped in TimeBudgetPools.
 //
 // This is done by disabling throttled queues and running
 // a special "heart beat" function |PumpThrottledTasks| which when run
 // temporarily enables throttled queues and inserts a fence to ensure tasks
 // posted from a throttled task run next time the queue is pumped.
@@ skipping 232 matching lines @@
 
   base::WeakPtrFactory<TaskQueueThrottler> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(TaskQueueThrottler);
 };
 
 }  // namespace scheduler
 }  // namespace blink
 
 #endif  // THIRD_PARTY_WEBKIT_SOURCE_PLATFORM_SCHEDULER_RENDERER_THROTTLING_HELPER_H_