Add font colour support to wxFontPickerCtrl.

Currently this is only really implemented under Windows, just as the colour
support in wxFontDialog, but make the API available under all platforms for
consistency.

Closes #11614.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@76160 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/fontpicker.h

@@ -41,6 +41,9 @@ public:
     virtual void SetSelectedFont(const wxFont &f)
         { m_selectedFont = f; UpdateFont(); }
 
+    virtual wxColour GetSelectedColour() const = 0;
+    virtual void SetSelectedColour(const wxColour &colour) = 0;
+
 protected:
 
     virtual void UpdateFont() = 0;
@@ -138,7 +141,15 @@ public:         // public API
     // sets currently displayed font
     void SetSelectedFont(const wxFont& f);
 
-    // set/get the max pointsize
+    // returns the selected color
+    wxColour GetSelectedColour() const
+        { return GetPickerWidget()->GetSelectedColour(); }
+
+    // sets the currently selected color
+    void SetSelectedColour(const wxColour& colour)
+        { GetPickerWidget()->SetSelectedColour(colour); }
+
+    // set/get the max point size
     void SetMaxPointSize(unsigned int max)
         { m_nMaxPointSize=max; }
     unsigned int GetMaxPointSize() const