Add OS X implementation of wxAppProgressIndicator.

Closes #16638.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@78499 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/msw/gauge.h

@@ -15,8 +15,6 @@
 
 extern WXDLLIMPEXP_DATA_CORE(const char) wxGaugeNameStr[];
 
-class WXDLLIMPEXP_FWD_CORE wxAppProgressIndicator;
-
 // Group box
 class WXDLLIMPEXP_CORE wxGauge : public wxGaugeBase
 {
@@ -73,8 +71,6 @@ private:
     void SetIndeterminateMode();
     void SetDeterminateMode();
 
-    wxAppProgressIndicator* m_appProgressIndicator;
-
     DECLARE_DYNAMIC_CLASS_NO_COPY(wxGauge)
 };