Make some Keyguard changes to accomodate screenshot testing

Also changed ClockSize to a kotlin enum

Bug: 326375986
Bug: 333389512
Test: atest SimpleClockScreenshotTest
Flag: ACONFIG com.android.systemui.migrate_clocks_to_blueprint STAGING
Change-Id: I744dadc4d4ef7cf3a24e939f2c89728bc8075f2c
46 files changed