[fix bug 918447] Main-nav border radius
[fix bug 918447] Main-nav border radius

akatsoulas/mozillians,mozilla/mozillians,akarki15/mozillians,chirilo/mozillians,hoosteeno/mozillians,justinpotts/mozillians,fxa90id/mozillians,johngian/mozillians,akarki15/mozillians,anistark/mozillians,chirilo/mozillians,justinpotts/mozillians,fxa90id/mozillians,johngian/mozillians,johngian/mozillians,justinpotts/mozillians,johngian/mozillians,mozilla/mozillians,chirilo/mozillians,safwanrahman/mozillians,mozilla/mozillians,akatsoulas/mozillians,anistark/mozillians,anistark/mozillians,brian-yang/mozillians,akatsoulas/mozillians,safwanrahman/mozillians,safwanrahman/mozillians,ChristineLaMuse/mozillians,hoosteeno/mozillians,brian-yang/mozillians,brian-yang/mozillians,akatsoulas/mozillians,mozilla/mozillians,justinpotts/mozillians,ChristineLaMuse/mozillians,akarki15/mozillians,ChristineLaMuse/mozillians,hoosteeno/mozillians,akarki15/mozillians,safwanrahman/mozillians,hoosteeno/mozillians,chirilo/mozillians,fxa90id/mozillians,fxa90id/mozillians,brian-yang/mozillians,anistark/mozillians