DcTracker: wait for default apn to disconnect before setting up new

Including the removal of a previous attempt to fix this issue:

Revert "Frameworks : Make sure a reply is sent when not provisioning default apn"

This reverts commit 8733a2d2a1c5c88f661c4d6947cc9eb8f27d4874.

Revert "DcTrackerBase: Dont provision APN if default is disconnecting"

This reverts commit cf13f20b88c5add9d2e8ea74b8fe9fbeb88101b2.

Change-Id: I8181dca843eb3de4be68c5b2be6aac9d81732558

Conflicts:
	src/java/com/android/internal/telephony/dataconnection/DcTrackerBase.java
DcTracker: Expedite data stall recovery

The current stall recovery process has a pending packet queue which
needs to fill up before a stall is determined. But that process is
also multi-step, and it is currently expecting that queue to fill
between steps.
Waiting for the unacknowledged packets to grow after running the
connection cleanup step looks like something that would never happen,
or would take a very long time to, so expedite the stall recovery after
it begins: if any single packet stalls and there's already a recovery
in progress, run the follow up step immediately.

Change-Id: Ib16b2c47b5c832a812c8bd2a3d940862741ed9db
SIMRecords: If there's no EF_SPN record, fallback to EF_PNN

Turns out some SIM (TMobile US, at least) don't fill in the SPN, but
do insert a PNN record for home network (which in the case of a non-MVNO
are the same. a MVNO should always have the SPN filled anyway).

Change-Id: I18388bb071a49698015c76abefb58798f800946c
Telephony: Scrub debug messages for identifiable information.

Change-Id: I70fd8d9b4900dc9e070be24e7efa8d3458caef99
Telephony: Close the FileReader when finished

Change-Id: I12865e8d974515d4f349d476bcf775e015008e16