force DPIScaleFactor to 1 on Mac

Change-Id: I37629e1ef18f9843fcbdd643d8aaee0b3c8baa73
remove osolete ifdef

now that the ScaleDPI is forced to 1 on mac there is no need
for these ifdef

Change-Id: I0ca3bc301b63f5f4c7d1eb36f27bc9b6ab41af29