Mms: Handle possible null array on sub id.

  In some scenarios (possibly even data corruption), the destPhoneId
  used to retrieve the sub id may not be valid anymore. This can
  happen when an mms fails to be received and handled correctly. Instead
  of leaving user in a broken state (ex: unable to open mms), handle
  the null array and log the error.

  Example trace:

  AndroidRuntime
  E  FATAL EXCEPTION: TransactionService
    E  Process: com.android.mms, PID: 6440
    E  java.lang.NullPointerException: Attempt to read from null array
    E      at com.android.mms.transaction.TransactionService.onNewIntent(TransactionServic
                           e.java:479)
    E      at com.android.mms.transaction.TransactionService$ServiceHandler.handleMessage(
                           TransactionService.java:934)
    E      at android.os.Handler.dispatchMessage(Handler.java:102)
    E      at android.os.Looper.loop(Looper.java:135)
    E      at android.os.HandlerThread.run(HandlerThread.java:61)

Change-Id: I20b32455f294f1fd5a31363fbefd0cc3337461ee