Move rotation methods to DisplayContent

This moves some of the rotation logic applied to displays
from WindowManagerService to DisplayContent. No changes in
logic.

Bug: 34242678
Test: android.server.cts.ActivityManagerDisplayTests
Test: #testRotationNotAffectingSecondaryScreen
Test: android.server.cts.ActivityManagerAppConfigurationTests
Change-Id: Ica8b5d700dea82edfc6b51b10be3362fc89854b0
4 files changed