Remove the last 2 uses of displayTopology flags

These are the last 2 direct uses of the flags. All other uses go through
the DesktopExperienceFlags, either directly or through
DisplayManagerFlag.

Fix: 413691958
Test: Build and presuibmit
Flag: EXEMPT (flag system)
Change-Id: I35e31fd3ff852641507b7d5ad4a471467617a199