Do not use hidden APIs in UserHandle/UserManager

1. UserHandle.<init>: replaced with UserHandle.of()
2. UserHandle.getCallingUserId: removed
2. UserManager.get(): replaced with getSystemService(Context.USER_SERVICE)

Bug: 137202333
Test: make
Change-Id: I5aeedfb204d0297ecf5a9f6758562fac24de6e9e
4 files changed