Revert of Make WebTraceLocation be an alias of tracked_objects::Location

components/scheduler/child/webthread_base.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 COMPONENTS_SCHEDULER_CHILD_WEBTHREAD_BASE_H_
 #define COMPONENTS_SCHEDULER_CHILD_WEBTHREAD_BASE_H_
 
 #include <map>
 #include <memory>
 
 #include "base/threading/thread.h"
 #include "components/scheduler/scheduler_export.h"
 #include "third_party/WebKit/public/platform/WebThread.h"
-#include "third_party/WebKit/public/platform/WebTraceLocation.h"
+
+namespace blink {
+class WebTraceLocation;
+}
 
 namespace scheduler {
 class SingleThreadIdleTaskRunner;
 
 class SCHEDULER_EXPORT WebThreadBase : public blink::WebThread {
  public:
   ~WebThreadBase() override;
 
   // blink::WebThread implementation.
   bool isCurrentThread() const override;
@@ skipping 30 matching lines @@
       base::TimeTicks deadline);
 
  private:
   typedef std::map<TaskObserver*, TaskObserverAdapter*> TaskObserverMap;
   TaskObserverMap task_observer_map_;
 };
 
 }  // namespace scheduler
 
 #endif  // COMPONENTS_SCHEDULER_CHILD_WEBTHREAD_BASE_H_