Merge changes Ic61819b8,I4149abe1,Ic738a6dd,I297faa26,Ib6a929ef, ...

* changes:
  Prevent PreCallActivity from showing in lockscreen if it is not started in the lockscreen
  Prevent change SIM icon from showing during a voicemail call
  Expose user home country code as public method in Mediator Interface.
  Update assisted dialing setting text.
  Contact list no longer jumps to the top when the cp2 database updates.
  Refactor DialpadFragment's DtmfKeyListener
  Adjust strings for select SIM dialog
  Add impressions for dual sim features