exposay: remove redundant NULL check in highlight_surface

exposay_highlight_surface() is called from exposay_pick(),
exposay_layout(), and exposay_maybe_move() where the esurface
parameter is already validated prior to the call.  This makes
the 'esurface' NULL check redundant.  This assumes any future
calls to exposay_highlight_surface() will also validate the
'esurface' parameter prior to the call.

This fixes the logic in exposay_highlight_surface so static
analyzers don't complain about the possibility that 'view'
might be NULL deref'd when a 'esurface' == NULL condition is
true.

Signed-off-by: U. Artie Eoff <ullysses.a.eoff@intel.com>
input-panel: validate return value of get_default_view

Signed-off-by: U. Artie Eoff <ullysses.a.eoff@intel.com>
shell: validate get_animation_type parameter

Signed-off-by: U. Artie Eoff <ullysses.a.eoff@intel.com>
shell: validate create_focus_surface results

Signed-off-by: U. Artie Eoff <ullysses.a.eoff@intel.com>