Nuke WebPassOwnPtr<T> and replace it with std::unique_ptr<T>.

components/scheduler/renderer/renderer_web_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 COMPONENTS_SCHEDULER_RENDERER_RENDERER_WEB_SCHEDULER_IMPL_H_
 #define COMPONENTS_SCHEDULER_RENDERER_RENDERER_WEB_SCHEDULER_IMPL_H_
 
 #include "components/scheduler/child/web_scheduler_impl.h"
 
 namespace scheduler {
 
 class RendererSchedulerImpl;
 
 class SCHEDULER_EXPORT RendererWebSchedulerImpl : public WebSchedulerImpl {
  public:
   explicit RendererWebSchedulerImpl(RendererSchedulerImpl* renderer_scheduler);
 
   ~RendererWebSchedulerImpl() override;
 
   // blink::WebScheduler implementation:
   void suspendTimerQueue() override;
   void resumeTimerQueue() override;
-  blink::WebPassOwnPtr<blink::WebViewScheduler> createWebViewScheduler(
+  std::unique_ptr<blink::WebViewScheduler> createWebViewScheduler(
       blink::WebView* web_view) override;
   void addPendingNavigation() override;
   void removePendingNavigation() override;
   void onNavigationStarted() override;
 
  private:
   RendererSchedulerImpl* renderer_scheduler_;  // NOT OWNED
 };
 
 }  // namespace scheduler
 
 #endif  // COMPONENTS_SCHEDULER_RENDERER_RENDERER_WEB_SCHEDULER_IMPL_H_