desktop:fixed richdir contextmenu 'delete' bug

when select more richdirs and items,
right click on richdir,and choose 'Delete',
the others item selected will not be deleted!

tower:https://tower.im/projects/8f19f0bf0e754f0b82ef2c24bc230973/todos/8dae180af2f14dc7bee642fea84be5ea/

Change-Id: Iac3a126a8616c68d69a2cfcecc1630af6dc1e867