Fix an NPE in WifiConfigStore

Disabling an invalid configuration causes Wifi service
to crash. This change gaurds against bad API call.

Bug: 18904771
Change-Id: I8d853b754cbd4163c17f3d53bf81dc7625c95466
1 file changed
tree: 1b56608bcc4ccf9074fb33cfc069c3dc8da3c81b
  1. service/