Record size of scroller that user scrolls

third_party/WebKit/Source/core/input/ScrollManager.h

 // Copyright 2016 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 ScrollManager_h
 #define ScrollManager_h
 
 #include "core/CoreExport.h"
 #include "core/page/EventWithHitTestResults.h"
 #include "platform/geometry/LayoutSize.h"
@@ skipping 60 matching lines @@
 
   // TODO(crbug.com/616491): Consider moving all gesture related functions to
   // another class.
 
   // Handle the provided scroll gesture event, propagating down to child frames
   // as necessary.
   WebInputEventResult handleGestureScrollEvent(const WebGestureEvent&);
 
   WebInputEventResult handleGestureScrollEnd(const WebGestureEvent&);
 
+  void recordScrollerSize(const LayoutObject&, const WebGestureDevice);
+
   bool isScrollbarHandlingGestures() const;
 
   // Returns true if the gesture event should be handled in ScrollManager.
   bool canHandleGestureEvent(const GestureEventWithHitTestResults&);
 
   // These functions are related to |m_resizeScrollableArea|.
   bool inResizeMode() const;
   void resize(const WebMouseEvent&);
   // Clears |m_resizeScrollableArea|. if |shouldNotBeNull| is true this
   // function DCHECKs to make sure that variable is indeed not null.
@@ skipping 49 matching lines @@
 
   Member<PaintLayerScrollableArea> m_resizeScrollableArea;
 
   LayoutSize
       m_offsetFromResizeCorner;  // In the coords of m_resizeScrollableArea.
 };
 
 }  // namespace blink
 
 #endif  // ScrollManager_h