Remove ScrollableArea::GetFrameViewBase and move ScheduleAnimation into subclasses.

third_party/WebKit/Source/core/frame/RootFrameViewport.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 RootFrameViewport_h
 #define RootFrameViewport_h
 
 #include "core/CoreExport.h"
 #include "platform/scroll/ScrollableArea.h"
 
@@ skipping 80 matching lines @@
   int VerticalScrollbarWidth(
       OverlayScrollbarClipBehavior =
           kIgnorePlatformOverlayScrollbarSize) const override;
   ScrollResult UserScroll(ScrollGranularity, const FloatSize&) override;
   bool ScrollAnimatorEnabled() const override;
   HostWindow* GetHostWindow() const override;
   void ServiceScrollAnimations(double) override;
   void UpdateCompositorScrollAnimations() override;
   void CancelProgrammaticScrollAnimation() override;
   ScrollBehavior ScrollBehaviorStyle() const override;
-  FrameViewBase* GetFrameViewBase() override;
   void ClearScrollableArea() override;
   LayoutBox* GetLayoutBox() const override;
   FloatQuad LocalToVisibleContentQuad(const FloatQuad&,
                                       const LayoutObject*,
                                       unsigned = 0) const final;
   RefPtr<WebTaskRunner> GetTimerTaskRunner() const final;
 
  private:
   RootFrameViewport(ScrollableArea& visual_viewport,
                     ScrollableArea& layout_viewport);
@@ skipping 23 matching lines @@
 
 DEFINE_TYPE_CASTS(RootFrameViewport,
                   ScrollableArea,
                   scrollableArea,
                   scrollableArea->IsRootFrameViewport(),
                   scrollableArea.IsRootFrameViewport());
 
 }  // namespace blink
 
 #endif  // RootFrameViewport_h