win32: fixed toolbar visibility checking
win32: fixed toolbar visibility checking

Signed-off-by: Cheng Sun <60571aabc0f1a69f92f406e14d30b962c321c67c@gmail.com>

chengsun/gtk-npapi-vlc,chengsun/gtk-npapi-vlc,chengsun/gtk-npapi-vlc,jamesbates/npapi-vlc,jamesbates/npapi-vlc,jamesbates/npapi-vlc