Moved display related getting of orientation into DisplayContent

5th step in trying to make WindowList private to DisplayContent.
Exact code to get orientation in WMS that is display specific
because it iterates over the window list into the DisplayContent
object.

Test: Manual testing and exiting test pass.
Change-Id: Iced72322cdebdde83882802af4a9decf323f20e1
2 files changed