AI 144395: am: CL 144257 am: CL 144256 Need to show opt-in screen for location collection.

  Added a screen to the setup wizard, after login, to ask user to
  opt-in for location collection.
  Added a dialog to Settings when user turns on Network location.
  Fixed a security permission issue in LocationManagerService related
  to this change.
  Original author: yamasani
  Merged from: //branches/cupcake/...
  Original author: android-build

Automated import of CL 144395