Linux: resolve issue compiling on mint 18.3

size_t wasn't declared. While this could be resolved differently,
convention is to include BKE after BLI.

source/blender/depsgraph/intern/eval/deg_eval_flush.cc

@@ -29,15 +29,15 @@
 #include <deque>
 #include <cmath>
 
-#include "BKE_object.h"
-#include "BKE_scene.h"
-
 #include "BLI_utildefines.h"
 #include "BLI_listbase.h"
 #include "BLI_math_vector.h"
 #include "BLI_task.h"
 #include "BLI_ghash.h"
 
+#include "BKE_object.h"
+#include "BKE_scene.h"
+
 extern "C" {
 #include "DNA_object_types.h"
 #include "DNA_scene_types.h"