Make WebTaskRunner ThreadSafeRefCounted

third_party/WebKit/Source/platform/mac/ScrollAnimatorMac.h

 /*
  * Copyright (C) 2010, 2011 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 67 matching lines @@
   RetainPtr<BlinkScrollbarPainterControllerDelegate>
       m_scrollbarPainterControllerDelegate;
   RetainPtr<BlinkScrollbarPainterDelegate> m_horizontalScrollbarPainterDelegate;
   RetainPtr<BlinkScrollbarPainterDelegate> m_verticalScrollbarPainterDelegate;
 
   void initialScrollbarPaintTask();
   TaskHandle m_initialScrollbarPaintTaskHandle;
 
   void sendContentAreaScrolledTask();
   TaskHandle m_sendContentAreaScrolledTaskHandle;
-  std::unique_ptr<WebTaskRunner> m_taskRunner;
+  RefPtr<WebTaskRunner> m_taskRunner;
   ScrollOffset m_contentAreaScrolledTimerScrollDelta;
 
   ScrollResult userScroll(ScrollGranularity,
                           const ScrollOffset& delta) override;
   void scrollToOffsetWithoutAnimation(const ScrollOffset&) override;
 
   void cancelAnimation() override;
 
   void contentAreaWillPaint() const override;
   void mouseEnteredContentArea() const override;
@@ skipping 21 matching lines @@
   void immediateScrollTo(const ScrollOffset&);
 
   bool m_haveScrolledSincePageLoad;
   bool m_needsScrollerStyleUpdate;
   IntRect m_visibleScrollerThumbRect;
 };
 
 }  // namespace blink
 
 #endif  // ScrollAnimatorMac_h