Allow DOZING->DREAMING

DreamManagerService can start a dream after the device has gone
to sleep, and after transitions have begun to DOZING. This should
prevent situations where the lockscreen content is still visible
after DREAMING has started.

Fixes: 383977604
Test: atest FromDozingTransitionInteractorTest
Flag: EXEMPT bugfix

Change-Id: I833578cad26c3f24cd372f047e12ba435d6ec0b0