[logging] Correct Enter Desktop windowing by Screen On

Previously Screen On to enter DW got logged as UNKNOWN reason often.

This happened when device gets locked on Screen off and instead of WAKE transition we have a BACK transition from keyguard.

Test: Tested locally on go/atomviewer and added unit tests
Bug: 361082583
Flag: EXEMPT bug fix
Change-Id: I994dbcbcc955aeb687a373113be91b11c2dc3a72