Re-order preferred starting window type.

Prioritize the snapshot starting window than allDrawn condition, so
there should show snapshot on phone when unlock keyguard or do quick
switch.
There should not affect low-ram device such as wear since there may
not capture snapshot, so there should still show splash screen starting
window for haven't drawn condition.
Also correct one of the shouldUseEmptySplashScreen condition that
launchedFromSystemSurface should only allowed when starting activity.

Test: Start app, go to lockscreen and unlock, verify there should choose
snapshot starting window.
Test: atest ActivityRecordTests SplashscreenTests
Bug: 176837715

Change-Id: I9112f93da35526f578df805dd5f126236c520d6a