Remove private wxDisclosureTriangle control.

Remove the private and undocumented control and it's usage in wxGenericCollapsiblePane. The class used a low resolution bitmap which looks bad on high resolution displays. The generic implementation using wxRendererNative::DrawCollapseButton() is better fit even on OS X.

include/wx/generic/collpaneg.h

@@ -14,9 +14,6 @@
 // forward declared
 class WXDLLIMPEXP_FWD_CORE wxCollapsibleHeaderCtrl;
 class WXDLLIMPEXP_FWD_CORE wxStaticLine;
-#if defined( __WXMAC__ ) && !defined(__WXUNIVERSAL__)
-class WXDLLIMPEXP_FWD_CORE wxDisclosureTriangle;
-#endif
 
 #include "wx/containr.h"
 
@@ -82,11 +79,7 @@ protected:
     int GetBorder() const;
 
     // child controls
-#if defined( __WXMAC__ ) && !defined(__WXUNIVERSAL__)
-    wxDisclosureTriangle *m_pButton;
-#else
     wxCollapsibleHeaderCtrl *m_pButton;
-#endif
     wxStaticLine *m_pStaticLine;
     wxWindow *m_pPane;
     wxSizer *m_sz;

include/wx/osx/button.h

@@ -56,40 +56,4 @@ protected:
     wxDECLARE_DYNAMIC_CLASS(wxButton);
 };
 
-// OS X specific class, not part of public wx API
-class WXDLLIMPEXP_CORE wxDisclosureTriangle : public wxControl
-{
-public:
-    wxDisclosureTriangle(wxWindow *parent,
-             wxWindowID id,
-             const wxString& label = wxEmptyString,
-             const wxPoint& pos = wxDefaultPosition,
-             const wxSize& size = wxDefaultSize,
-             long style = wxBORDER_NONE,
-             const wxValidator& validator = wxDefaultValidator,
-             const wxString& name = wxButtonNameStr)
-    {
-        Create(parent, id, label, pos, size, style, validator, name);
-    }
-
-    bool Create(wxWindow *parent,
-                wxWindowID id,
-                const wxString& label = wxEmptyString,
-                const wxPoint& pos = wxDefaultPosition,
-                const wxSize& size = wxDefaultSize,
-                long style = wxBORDER_NONE,
-                const wxValidator& validator = wxDefaultValidator,
-                const wxString& name = wxButtonNameStr);
-
-    void SetOpen( bool open );
-    bool IsOpen() const;
-
-    // osx specific event handling common for all osx-ports
-
-    virtual bool        OSXHandleClicked( double timestampsec );
-
-protected:
-    virtual wxSize DoGetBestSize() const ;
-};
-
 #endif // _WX_OSX_BUTTON_H_