qt4: Add a 'virtual vs Q_DECL_OVERRIDE' section
qt4: Add a 'virtual vs Q_DECL_OVERRIDE' section

This should explain when to use the virtual keyword or the
Q_DECL_OVERRIDE macros on virtual function declarations.

Signed-off-by: Tristan Matthews <58557b70081517323d8b069e20d681de970f25f5@gmail.com>

krichter722/vlc,xkfz007/vlc,vlc-mirror/vlc,xkfz007/vlc,shyamalschandra/vlc,krichter722/vlc,krichter722/vlc,krichter722/vlc,shyamalschandra/vlc,xkfz007/vlc,shyamalschandra/vlc,shyamalschandra/vlc,shyamalschandra/vlc,vlc-mirror/vlc,xkfz007/vlc,vlc-mirror/vlc,krichter722/vlc,vlc-mirror/vlc,shyamalschandra/vlc,xkfz007/vlc,vlc-mirror/vlc,krichter722/vlc,vlc-mirror/vlc,shyamalschandra/vlc,vlc-mirror/vlc,xkfz007/vlc,krichter722/vlc,xkfz007/vlc