SF: Test coverage for display transaction state changes

Add a final set of tests to cover other display state change handling
in SurfaceFlinger::handleTransactionLocked(eDisplayTransactionNeeded)

Test: libsurfaceflinger_unittest passes on Pixel XL
Bug: 74827900
Change-Id: Ie2394b9c202a7518183d8293218b51fe6fd01cd8
1 file changed