Add wxFontDialog::RestrictSelection() to disallow raster fonts

Under MSW it is possible to restrict the native font dialog to showing
only scalable fonts only, disallowing the raster fonts, so add a method
to wxFontDialog exposing this functionality in wxWidgets API.

Closes https://github.com/wxWidgets/wxWidgets/pull/1926

Closes #16988.

include/wx/fontdata.h

@@ -12,6 +12,14 @@
 #include "wx/colour.h"
 #include "wx/encinfo.h"
 
+// Possible values for RestrictSelection() flags.
+enum
+{
+    wxFONTRESTRICT_NONE         = 0,
+    wxFONTRESTRICT_SCALABLE     = 1 << 0,
+    wxFONTRESTRICT_FIXEDPITCH   = 1 << 1
+};
+
 class WXDLLIMPEXP_CORE wxFontData : public wxObject
 {
 public:
@@ -33,6 +41,9 @@ public:
     void EnableEffects(bool flag) { m_enableEffects = flag; }
     bool GetEnableEffects() const { return m_enableEffects; }
 
+    void RestrictSelection(int flags) { m_restrictSelection = flags; }
+    int  GetRestrictSelection() const { return m_restrictSelection; }
+
     void SetInitialFont(const wxFont& font) { m_initialFont = font; }
     wxFont GetInitialFont() const { return m_initialFont; }
 
@@ -63,6 +74,7 @@ public:
 private:
     wxFontEncoding       m_encoding;
     wxNativeEncodingInfo m_encodingInfo;
+    int                  m_restrictSelection;
 
     wxDECLARE_DYNAMIC_CLASS(wxFontData);
 };