Kill unused SfxHistoryToolBoxControl_Impl.

Change-Id: I03655bb502d6480d8f7f3f1adef17d8f635b8ed9

include/sfx2/tbxctrl.hxx

@@ -351,23 +351,6 @@ private:
     sal_Bool                m_bShowMenuImages;
 };
 
-class SfxHistoryToolBoxControl_Impl : public SfxToolBoxControl
-{
-    Timer                   aTimer;
-
-private:
-                            DECL_LINK( Timeout, Timer * );
-
-protected:
-    virtual void            Click( );
-    using SfxToolBoxControl::Select;
-    virtual void            Select( sal_Bool );
-
-public:
-                            SFX_DECL_TOOLBOX_CONTROL();
-                            SfxHistoryToolBoxControl_Impl( sal_uInt16 nId, ToolBox& rBox );
-};
-
 class SfxReloadToolBoxControl_Impl : public SfxToolBoxControl
 {
     protected: