compositor: Set pointer->current before calling focus handler
compositor: Set pointer->current before calling focus handler

The grab interface handlers all expect pointer->current to identify
the surface under the pointer regardless of grabs etc.  Thus, we need
to set it before calling the focus handler.

xorgy/weston,krezovic/weston,mchalupa/weston,Gnurou/weston,xorgy/weston,jonnylamb/weston,eyolfson/weston,giucam/weston,jonnylamb/weston,Fantu/compositor-spice,giucam/weston,sir-murray/weston,Tarnyko/weston-xdg_surface_present,Gnurou/weston,Fantu/compositor-spice,sir-murray/weston,kwm81/weston,krezovic/weston,udoprog/weston,udoprog/weston,Tarnyko/weston-xdg_surface_present,Fantu/compositor-spice,kwm81/weston,mchalupa/weston,eyolfson/weston