Reland of place pinch scrollbars with regular scrollbars.

Source/core/frame/VisualViewport.h

Index: Source/core/frame/VisualViewport.h
diff --git a/Source/core/frame/VisualViewport.h b/Source/core/frame/VisualViewport.h
index e1831b29873c518e99eede32574e55f6ba43dc54..0b05f5252072b89119363e970142c0ec719d9762 100644
--- a/Source/core/frame/VisualViewport.h
+++ b/Source/core/frame/VisualViewport.h
@@ -87,6 +87,8 @@
         return m_innerViewportScrollLayer.get();
     }
 
+    void initializeScrollbars();
+
     // Sets the location of the visual viewport relative to the outer viewport. The
     // coordinates are in partial CSS pixels.
     void setLocation(const FloatPoint&);
@@ -195,6 +197,8 @@
 private:
     explicit VisualViewport(FrameHost&);
 
+    bool visualViewportSuppliesScrollbars() const;
+
     // GraphicsLayerClient implementation.
     void paintContents(const GraphicsLayer*, GraphicsContext&, GraphicsLayerPaintingPhase, const IntRect& inClip) override;
     String debugName(const GraphicsLayer*) override;