Check TelephonyManager#getDeviceId Returns Null

TelephonyManager#getDeviceId should return null for non-telephony
devices. Add that assertion to the test. Leave the tests that
check that Wifi is supported on a non-telephony device though,
because at least one form of wireless data networking must be
supported...

Change-Id: If4752df120be28526d3f585d0896fb8a1e0bee81
1 file changed