Add support for handling mobile provisioning networks.

When a sim is new or it has expired it needs to be provisioned
with the carrier. Basically provisioning is associating a sim with
a user account. When a sim isn't provisioned then operators will
restrict access to the network and only allow certain addresses
or services to be used.

This set of changes allows two types of provisioning networks to be
recognized. The first is a network that causes all DNS lookups to be
redirected to a different address than was intended. This is exemplified
by how T-Mobile works.

The second technique uses a special apn for provisioning. An example is
AT&T where lwaactivate is the provisioning apn and broadband is the
normal apn. We first try broadband and if we are unable to connect we
try lwaactivate. When we see the activate we identify it as special and
the ApnContext.isProvisioningApn will return true.

In the future our plan is to create a new network type that can be added
to the apn list, but for now it identified by name.

Here is a list of significant changes:

 - CaptivePortalTracker now only test WiFi networks instead of all networks
 - checkMobileProvisioning checks for provisioning networks and doesn't
   try to ping.
 - IConnectivityManager.aidl changes:
   * getProvisioningOrActiveNetworkInfo was added to and used by Manage
     mobile plan in WirelessSettings so even when there is no active
     network it will still allow provisioning. Otherwise it would report
     no internet connection.
   * setSignInErrorNotificationVisible is used by both
     CaptiviePortalTracker and checkMobileProvisioning so they use the
     same code for the notifications.
   * checkMobileProvisioning was simplified to have only a timeout as
     returning the result is now harder as we abort simultaneous call
     otherwise we'd could get into loops because we now check every time
     we connect to mobile.
 - Enhanced MDST to handle the provisioning network.
 - Added CONNECTED_TO_PROVISIONING_NETWORK to NetworkInfo to make a new
   state so we don't announce to the world we're connected.
 - TelephonyIntents.ACTION_DATA_CONNECTION_CONNECTED_TO_PROVISIONING_APN
   is sent by the low level data connection code to notify Connectivity
   Service that a provisioning apn has connected. This allows CS to
   handle the connection differently than a normal connection.

Bug: 10328264
Change-Id: I3925004011bb1243793c4c1b963d923dc2b00cb5