added wxBitmap::CopyFromIcon to wxGTK

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@11680 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/gtk/bitmap.h

@@ -84,6 +84,9 @@ public:
     
     wxImage ConvertToImage() const;
 
+    // copies the contents and mask of the given (colour) icon to the bitmap
+    virtual bool CopyFromIcon(const wxIcon& icon);
+
     wxMask *GetMask() const;
     void SetMask( wxMask *mask );