Reset drag state variables on mouse up

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

 /*
  * Copyright (C) 2006, 2007, 2009, 2010, 2011 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 275 matching lines @@
     //     Same applied to dispatchMouseEvent() above.
     WebInputEventResult updatePointerTargetAndDispatchEvents(const AtomicString& mouseEventType, Node* target,
         int clickCount, const PlatformMouseEvent&);
 
     WebInputEventResult dispatchDragEvent(const AtomicString& eventType, Node* target, const PlatformMouseEvent&, DataTransfer*);
 
     void clearDragDataTransfer();
 
     bool handleDrag(const MouseEventWithHitTestResults&, DragInitiator);
     bool tryStartDrag(const MouseEventWithHitTestResults&);
+
+    // Clears drag target and related states. It is called when drag is done or canceled.
     void clearDragState();
 
+    // Resets the state that indicates the next events could cause a drag. It is called when
+    // we realize the next events should not cause drag based on the drag heuristics.
+    void clearDragHeuristicState();
+
     WebInputEventResult dispatchDragSrcEvent(const AtomicString& eventType, const PlatformMouseEvent&);
 
     bool dragHysteresisExceeded(const IntPoint&) const;
 
     WebInputEventResult passMousePressEventToSubframe(MouseEventWithHitTestResults&, LocalFrame* subframe);
     WebInputEventResult passMouseMoveEventToSubframe(MouseEventWithHitTestResults&, LocalFrame* subframe, HitTestResult* hoveredNode = nullptr);
     WebInputEventResult passMouseReleaseEventToSubframe(MouseEventWithHitTestResults&, LocalFrame* subframe);
 
     bool passMousePressEventToScrollbar(MouseEventWithHitTestResults&);
 
@@ skipping 89 matching lines @@
 
     // Set on GestureTapDown if the |pointerdown| event corresponding to the
     // triggering |touchstart| event was canceled. This suppresses mouse event
     // firing for the current gesture sequence (i.e. until next GestureTapDown).
     bool m_suppressMouseEventsFromGestures;
 };
 
 } // namespace blink
 
 #endif // EventHandler_h