Shading: Add object color to Object Info node.

The object color property is added as an additional output in
the Object Info node.

Reviewers: brecht

Differential Revision: https://developer.blender.org/D5554

source/blender/draw/intern/draw_manager.c

@@ -603,6 +603,7 @@ static DRWCallState *draw_unit_state_create(void)
 
   state->ob_index = 0;
   state->ob_random = 0.0f;
+  copy_v3_fl(state->ob_color, 1.0f);
 
   /* TODO(fclem) get rid of this. */
   state->culling = BLI_memblock_alloc(DST.vmempool->cullstates);