ivi-shell: handle subsurfaces for mouse/touch activation
The surface of the focus_view may be a subsurface. So get the corresponding main surface first.
Without this get_ivi_shell_surface(), will cast committed_private (which is a weston_subsurface object) to ivi_shell_surface. Weston crashes shortly afterwards.
Signed-off-by: Michael Olbrich m.olbrich@pengutronix.de