Code review comment for lp://staging/~phablet-team/network-manager/lp1445080-wily

Updated to fold the core changes into existing patches, created new patches for core changes, and ensure that new patches have DEP-3 headers.

Yes, some of the core changes were discussed upstream, but as I wasn't getting much traction with upstream and the changes needed to land for phone networking stabilization, the changes were landed in the phone overlay PPA after being reviewed and thoroughly tested.

> What is the likely impact on non-ofono modems of the changes to nm_device_modem to not return that connections are unavailable when the modem is still in NM_MODEM_STATE_INITIALIZING state, for example?

Actually, that's not how the change works. The change ensures that devices with a modem_state <= SEARCHING are considered unavailable. As INITIALIZING is less than SEARCHING, modems in this state will still be considered unavailable. This is consistent with the function documentation for nm_device_is_available () and nm_device_connection_is_available (). Note, this hasn't been tested on non-ofono modems, so this will need to be done. If problems arise, then we will need to add a hook so that NMModemOfono can implement a stricter policy than NMDeviceModem for availability.