_set_button_page(): clear IG plane when page changes
_set_button_page(): clear IG plane when page changes

zxlooong/libbluray,EdwardNewK/libbluray,Distrotech/libbluray,Distrotech/libbluray,EdwardNewK/libbluray,Distrotech/libbluray,ace20022/libbluray,pingflood/libbluray,Azzuro/libbluray,koying/libbluray,Distrotech/libbluray,vlc-mirror/libbluray,tourettes/libbluray,vlc-mirror/libbluray,UIKit0/libbluray,pingflood/libbluray,UIKit0/libbluray,mwgoldsmith/bluray,UIKit0/libbluray,ShiftMediaProject/libbluray,ace20022/libbluray,mwgoldsmith/bluray,mwgoldsmith/bluray,Azzuro/libbluray,ace20022/libbluray,EdwardNewK/libbluray,Azzuro/libbluray,tourettes/libbluray,tourettes/libbluray,UIKit0/libbluray,vlc-mirror/libbluray,vlc-mirror/libbluray,mwgoldsmith/bluray,pingflood/libbluray,zxlooong/libbluray,ace20022/libbluray,koying/libbluray,EdwardNewK/libbluray,tourettes/libbluray,Azzuro/libbluray,ShiftMediaProject/libbluray,koying/libbluray,ShiftMediaProject/libbluray,koying/libbluray,ShiftMediaProject/libbluray,zxlooong/libbluray