blink: Cleanup class forward declarations

third_party/WebKit/Source/platform/scheduler/renderer/web_view_scheduler_impl.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_WEB_VIEW_SCHEDULER_IMPL_H_
 #define THIRD_PARTY_WEBKIT_SOURCE_PLATFORM_SCHEDULER_RENDERER_WEB_VIEW_SCHEDULER_IMPL_H_
 
 #include <memory>
 #include <set>
 #include <string>
 
 #include "base/macros.h"
 #include "public/platform/scheduler/base/task_queue.h"
 #include "public/platform/WebCommon.h"
 #include "public/platform/WebScheduler.h"
 #include "public/platform/WebViewScheduler.h"
 #include "platform/scheduler/renderer/task_queue_throttler.h"
 
 namespace base {
 namespace trace_event {
 class BlameContext;
 }  // namespace trace_event
-class SingleThreadTaskRunner;
 }  // namespace base
 
 namespace blink {
 namespace scheduler {
 
 class RendererSchedulerImpl;
 class WebFrameSchedulerImpl;
 
 class BLINK_PLATFORM_EXPORT WebViewSchedulerImpl : public WebViewScheduler {
  public:
@@ skipping 52 matching lines @@
   TaskQueueThrottler::TimeBudgetPool*
       background_time_budget_pool_;  // Not owned.
 
   DISALLOW_COPY_AND_ASSIGN(WebViewSchedulerImpl);
 };
 
 }  // namespace scheduler
 }  // namespace blink
 
 #endif  // THIRD_PARTY_WEBKIT_SOURCE_PLATFORM_SCHEDULER_RENDERER_WEB_VIEW_SCHEDULER_IMPL_H_