Fix inconsistent function declarations in documentation

Mostly remove the virtual keyword where the actual implementation isn't
virtual.

interface/wx/html/winpars.h

@@ -59,7 +59,7 @@ public:
         Assigns @a parser to this handler. Each @b instance of handler
         is guaranteed to be called only from the one parser.
     */
-    virtual void SetParser(wxHtmlWinParser* parser);
+    virtual void SetParser(wxHtmlParser* parser);
 
 protected:
     /**