Add a ve direction class to all surfaces

Previously we were relying on a body ltr/rtl class which only
exists in MW.

Also position context relative to UI surface not CE surface
to match shields (in practice they have the same position).

Bug: 66494
Change-Id: If14e91ce135fdf15a7715fb7907e957abae79581
Merge "Add a ve direction class to all surfaces"