Don't unconditionally disable dimming for transitions

This effectively reverts Iff541c21deb1ab483f80912c4dfd989ade6d1727, as
SurfaceFlinger now is more intelligent about not dimming SDR content
whne it doesn't have to. This behavior is also flag-guarded in
SurfaceFlinger

Bug: 293560925
Bug: 298492174
Bug: 299055884
Flag: Exempt
Test: screen rotation with and without HDR playback
Test: systemui jank metrics
Change-Id: I631fb32231dd933d9bd65619606eab80c725ff05