rotation: support for zombie ec

rotation: support for zombie ec

Occasionally, some client destroys only the xdg_surface and
keeps the wl_surface. In this case, E20 has the zombie ec for
maintaining of this kind of client. If the zombie ec is going
to be alive again (it means that client tries to show window),
then the zombie ec has the unmap state on the
E_COMP_OBJECT_INTERCEPT_HOOK_SHOW_HELPER handler. So fg_ec of
rotation module can not be changed to activated ec even if it
is shown on the screen.

Thus, we need to use a new hook for changing to right fg_ec of
rotation module in this case. E_POL_VIS_HOOK_TYPE_FG_SET is
good point to be called after E_COMP_OBJECT_INTERCEPT_HOOK_SHOW_HELPER
hook and given ec has always mapped state.

Change-Id: I6369d55e8198df567225fda2c25aa0de28e2f7f5