Generalize browser controls adjustment for arbitrary scrollers.

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 399 matching lines @@
   // Sets the tickmarks for the FrameView, overriding the default behavior
   // which is to display the tickmarks corresponding to find results.
   // If |m_tickmarks| is empty, the default behavior is restored.
   void setTickmarks(const Vector<IntRect>& tickmarks) {
     m_tickmarks = tickmarks;
     invalidatePaintForTickmarks();
   }
 
   void invalidatePaintForTickmarks();
 
-  // Since the compositor can resize the viewport due to browser controls and
-  // commit scroll offsets before a WebView::resize occurs, we need to adjust
-  // our scroll extents to prevent clamping the scroll offsets.
-  void setBrowserControlsViewportAdjustment(float);
-  IntSize browserControlsSize() const {
-    return IntSize(0, ceilf(m_browserControlsViewportAdjustment));
-  }
-
   IntSize maximumScrollOffsetInt() const override;
 
   // ScrollableArea interface
   void getTickmarks(Vector<IntRect>&) const override;
   IntRect scrollableAreaBoundingBox() const override;
   bool scrollAnimatorEnabled() const override;
   bool usesCompositedScrolling() const override;
   bool shouldScrollOnMainThread() const override;
   PaintLayer* layer() const override;
   GraphicsLayer* layerForScrolling() const override;
@@ skipping 626 matching lines @@
   float m_inputEventsScaleFactorForEmulation;
 
   IntSize m_layoutSize;
   IntSize m_initialViewportSize;
   bool m_layoutSizeFixedToFrameSize;
 
   Timer<FrameView> m_didScrollTimer;
 
   Vector<IntRect> m_tickmarks;
 
-  float m_browserControlsViewportAdjustment;
-
   bool m_needsUpdateWidgetGeometries;
 
 #if ENABLE(ASSERT)
   // Verified when finalizing.
   bool m_hasBeenDisposed;
 #endif
 
   ScrollbarMode m_horizontalScrollbarMode;
   ScrollbarMode m_verticalScrollbarMode;
 
@@ skipping 119 matching lines @@
                   widget.isFrameView());
 DEFINE_TYPE_CASTS(FrameView,
                   ScrollableArea,
                   scrollableArea,
                   scrollableArea->isFrameView(),
                   scrollableArea.isFrameView());
 
 }  // namespace blink
 
 #endif  // FrameView_h