Remove lock icon from AOD

 - Make AOD can not display lock icon
 - Since AOD will display lock icon a while when notification(plusing) coming, remove plusing method to make it won't display lock icon.

Bug: 153947852
Test: atest LockscreenIconControllerTest and manually
Change-Id: Idb9a133ec418805b6b620688a35d1b3e3e7cc08b
3 files changed