For Wayland, we want to have everything possible in terms of the frame
rect, or "window geometry" as the Wayland protocol calls it, in order
to properly eliminate some flashing when changing states to fullscreen
or similar.

For this, we need to heavily refactor how the code is structured, and
make it so that meta_window_move_resize_internal is specified in terms
of the frame rect coordinate space, and transforming all entry points
to meta_window_move_resize_internal.

This is a big commit that's hard to tear apart. I tried to split it
as best I can, but there's still just a large amount of changes that
need to happen at once.

Expect some regressions from this. Sorry for any temporary regression
that this might cause.