Made PlatformWheelEvent a subclass of PlatformMouseEvent.

third_party/WebKit/Source/platform/PlatformWheelEvent.h

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 #ifndef PlatformWheelEvent_h
 #define PlatformWheelEvent_h
 
 #include "platform/PlatformEvent.h"
+#include "platform/PlatformMouseEvent.h"
 #include "platform/geometry/IntPoint.h"
 
 namespace blink {
 
 // Wheel events come in two flavors:
 // The ScrollByPixelWheelEvent is a fine-grained event that specifies the precise number of pixels to scroll. It is sent directly by MacBook touchpads on OS X,
 // and synthesized in other cases where platforms generate line-by-line scrolling events.
 // The ScrollByPageWheelEvent indicates that the wheel event should scroll an entire page. In this case WebCore's built in paging behavior is used to page
 // up and down (you get the same behavior as if the user was clicking in a scrollbar track to page up or page down).
 enum PlatformWheelEventGranularity {
     ScrollByPageWheelEvent,
     ScrollByPixelWheelEvent,
 };
 
 #if OS(MACOSX)
 enum PlatformWheelEventPhase {
     PlatformWheelEventPhaseNone        = 0,
     PlatformWheelEventPhaseBegan       = 1 << 0,
     PlatformWheelEventPhaseStationary  = 1 << 1,
     PlatformWheelEventPhaseChanged     = 1 << 2,
     PlatformWheelEventPhaseEnded       = 1 << 3,
     PlatformWheelEventPhaseCancelled   = 1 << 4,
     PlatformWheelEventPhaseMayBegin    = 1 << 5,
 };
 #endif
 
-class PlatformWheelEvent : public PlatformEvent {
+class PlatformWheelEvent : public PlatformMouseEvent {
 public:
     PlatformWheelEvent()
-        : PlatformEvent(PlatformEvent::Wheel)
+        : PlatformMouseEvent(PlatformEvent::Wheel)
         , m_deltaX(0)
         , m_deltaY(0)
         , m_wheelTicksX(0)
         , m_wheelTicksY(0)
         , m_granularity(ScrollByPixelWheelEvent)
         , m_hasPreciseScrollingDeltas(false)
         , m_resendingPluginId(-1)
         , m_railsMode(RailsModeFree)
         , m_dispatchType(Blocking)
 #if OS(MACOSX)
         , m_phase(PlatformWheelEventPhaseNone)
         , m_momentumPhase(PlatformWheelEventPhaseNone)
 #endif
     {
     }
 
-    const IntPoint& position() const { return m_position; } // PlatformWindow coordinates.
-    const IntPoint& globalPosition() const { return m_globalPosition; } // Screen coordinates.
-
     float deltaX() const { return m_deltaX; }
     float deltaY() const { return m_deltaY; }
 
     float wheelTicksX() const { return m_wheelTicksX; }
     float wheelTicksY() const { return m_wheelTicksY; }
 
     PlatformWheelEventGranularity granularity() const { return m_granularity; }
 
     bool hasPreciseScrollingDeltas() const { return m_hasPreciseScrollingDeltas; }
     void setHasPreciseScrollingDeltas(bool b) { m_hasPreciseScrollingDeltas = b; }
     int resendingPluginId() const { return m_resendingPluginId; }
     RailsMode getRailsMode() const { return m_railsMode; }
     DispatchType dispatchType() const { return m_dispatchType; }
     bool cancelable() const { return m_dispatchType == PlatformEvent::Blocking; }
 #if OS(MACOSX)
     PlatformWheelEventPhase phase() const { return m_phase; }
     PlatformWheelEventPhase momentumPhase() const { return m_momentumPhase; }
 #endif
 
 protected:
-    IntPoint m_position;
-    IntPoint m_globalPosition;
     float m_deltaX;
     float m_deltaY;
     float m_wheelTicksX;
     float m_wheelTicksY;
     PlatformWheelEventGranularity m_granularity;
     bool m_hasPreciseScrollingDeltas;
     int m_resendingPluginId;
     RailsMode m_railsMode;
     DispatchType m_dispatchType;
 #if OS(MACOSX)
     PlatformWheelEventPhase m_phase;
     PlatformWheelEventPhase m_momentumPhase;
 #endif
 };
 
 } // namespace blink
 
 #endif // PlatformWheelEvent_h