Move middle-click autoscroll to synthetic fling.

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 <deque>
 #include "core/CoreExport.h"
 #include "core/page/EventWithHitTestResults.h"
@@ skipping 24 matching lines @@
     : public GarbageCollectedFinalized<ScrollManager> {
   WTF_MAKE_NONCOPYABLE(ScrollManager);
 
  public:
   explicit ScrollManager(LocalFrame&);
   DECLARE_TRACE();
 
   void Clear();
 
   bool MiddleClickAutoscrollInProgress() const;
+  void StopMiddleClickAutoscroll();
   AutoscrollController* GetAutoscrollController() const;
   void StopAutoscroll();
 
   // Performs a chaining logical scroll, within a *single* frame, starting
   // from either a provided starting node or a default based on the focused or
   // most recently clicked node, falling back to the frame.
   // Returns true if the scroll was consumed.
   // direction - The logical direction to scroll in. This will be converted to
   //             a physical direction for each LayoutBox we try to scroll
   //             based on that box's writing mode.
@@ skipping 91 matching lines @@
 
   Member<PaintLayerScrollableArea> resize_scrollable_area_;
 
   LayoutSize
       offset_from_resize_corner_;  // In the coords of m_resizeScrollableArea.
 };
 
 }  // namespace blink
 
 #endif  // ScrollManager_h