Revert "MainFrame scrollbars should work with RFV instead of FV"

third_party/WebKit/Source/core/frame/FrameView.h

 /*
    Copyright (C) 1997 Martin Jones (mjones@kde.org)
              (C) 1998 Waldo Bastian (bastian@kde.org)
              (C) 1998, 1999 Torben Weis (weis@kde.org)
              (C) 1999 Lars Knoll (knoll@kde.org)
              (C) 1999 Antti Koivisto (koivisto@kde.org)
    Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights
    reserved.
 
    This library is free software; you can redistribute it and/or
@@ skipping 447 matching lines @@
   // cross-platform Scrollbars. These functions can be used to obtain those
   // scrollbars.
   Scrollbar* horizontalScrollbar() const override {
     return m_scrollbarManager.horizontalScrollbar();
   }
   Scrollbar* verticalScrollbar() const override {
     return m_scrollbarManager.verticalScrollbar();
   }
   LayoutScrollbarPart* scrollCorner() const override { return m_scrollCorner; }
 
-  void updateScrollbars() override;
-
   void positionScrollbarLayers();
 
   // Functions for setting and retrieving the scrolling mode in each axis
   // (horizontal/vertical). The mode has values of AlwaysOff, AlwaysOn, and
   // Auto. AlwaysOff means never show a scrollbar, AlwaysOn means always show a
   // scrollbar.  Auto means show a scrollbar only when one is needed.
   // Note that for platforms with native widgets, these modes are considered
   // advisory. In other words the underlying native widget may choose not to
   // honor the requested modes.
   void setScrollbarModes(ScrollbarMode horizontalMode,
@@ skipping 287 matching lines @@
   ScrollBehavior scrollBehaviorStyle() const override;
 
   void scrollContentsIfNeeded();
 
   enum ComputeScrollbarExistenceOption { FirstPass, Incremental };
   void computeScrollbarExistence(
       bool& newHasHorizontalScrollbar,
       bool& newHasVerticalScrollbar,
       const IntSize& docSize,
       ComputeScrollbarExistenceOption = FirstPass) const;
+  void updateScrollbarGeometry();
 
+  // Called to update the scrollbars to accurately reflect the state of the
+  // view.
+  void updateScrollbars();
   void updateScrollbarsIfNeeded();
 
   class InUpdateScrollbarsScope {
     STACK_ALLOCATED();
 
    public:
     explicit InUpdateScrollbarsScope(FrameView* view)
         : m_scope(&view->m_inUpdateScrollbars, true) {}
 
    private:
@@ skipping 12 matching lines @@
    public:
     ScrollbarManager(FrameView& scroller) : blink::ScrollbarManager(scroller) {}
 
     void setHasHorizontalScrollbar(bool hasScrollbar) override;
     void setHasVerticalScrollbar(bool hasScrollbar) override;
 
     // TODO(ymalik): This should be hidden and all calls should go through
     // setHas*Scrollbar functions above.
     Scrollbar* createScrollbar(ScrollbarOrientation) override;
 
-    // Updates the scrollbar geometry given the size of the frame view rect.
-    void updateScrollbarGeometry(IntSize viewSize);
-
-    ScrollableArea* scrollableArea() const;
-
    protected:
     void destroyScrollbar(ScrollbarOrientation) override;
   };
 
   void updateScrollOffset(const ScrollOffset&, ScrollType) override;
 
   void updateLifecyclePhasesInternal(
       DocumentLifecycle::LifecycleState targetState);
 
   void invalidateTreeIfNeededRecursive();
@@ skipping 59 matching lines @@
   void setFragmentAnchor(Node*);
   void scrollToFragmentAnchor();
   void didScrollTimerFired(TimerBase*);
 
   void updateLayersAndCompositingAfterScrollIfNeeded(
       const ScrollOffset& scrollDelta);
 
   static bool computeCompositedSelection(LocalFrame&, CompositedSelection&);
   void updateCompositedSelectionIfNeeded();
 
+  // Returns true if the FrameView's own scrollbars overlay its content when
+  // visible.
+  bool hasOverlayScrollbars() const;
+
   // Returns true if the frame should use custom scrollbars. If true, one of
   // either |customScrollbarElement| or |customScrollbarFrame| will be set to
   // the element or frame which owns the scrollbar with the other set to null.
   bool shouldUseCustomScrollbars(Element*& customScrollbarElement,
                                  LocalFrame*& customScrollbarFrame) const;
 
   // Returns true if a scrollbar needs to go from native -> custom or vice
   // versa.
   bool needsScrollbarReconstruction() const;
 
@@ skipping 243 matching lines @@
                   widget.isFrameView());
 DEFINE_TYPE_CASTS(FrameView,
                   ScrollableArea,
                   scrollableArea,
                   scrollableArea->isFrameView(),
                   scrollableArea.isFrameView());
 
 }  // namespace blink
 
 #endif  // FrameView_h