create BKE_scene_layer_active

source/blender/blenkernel/BKE_layer.h

@@ -54,6 +54,7 @@ struct Scene;
 struct SceneCollection;
 struct SceneLayer;
 
+struct SceneLayer *BKE_scene_layer_active(struct Scene *scene);
 struct SceneLayer *BKE_scene_layer_add(struct Scene *scene, const char *name);
 
 bool BKE_scene_layer_remove(struct Main *bmain, struct Scene *scene, struct SceneLayer *sl);

source/blender/blenkernel/intern/context.c

@@ -914,10 +914,7 @@ SceneLayer *CTX_data_scene_layer(const bContext *C)
 		return sl;
 	}
 	else {
-		Scene *scene = CTX_data_scene(C);
-		sl = BLI_findlink(&scene->render_layers, scene->active_layer);
-		BLI_assert(sl);
-		return sl;
+		return BKE_scene_layer_active(CTX_data_scene(C));
 	}
 }
 

source/blender/blenkernel/intern/layer.c

@@ -57,6 +57,16 @@ static void object_bases_Iterator_next(Iterator *iter, const int flag);
 
 /* RenderLayer */
 
+/**
+ * Returns the SceneLayer to be used for rendering
+ */
+SceneLayer *BKE_scene_layer_active(struct Scene *scene)
+{
+	SceneLayer *sl = BLI_findlink(&scene->render_layers, scene->active_layer);
+	BLI_assert(sl);
+	return sl;
+}
+
 /**
  * Add a new renderlayer
  * by default, a renderlayer has the master collection

source/blender/editors/render/render_shading.c

@@ -653,7 +653,7 @@ void SCENE_OT_render_layer_add(wmOperatorType *ot)
 static int render_layer_remove_exec(bContext *C, wmOperator *UNUSED(op))
 {
 	Scene *scene = CTX_data_scene(C);
-	SceneLayer *sl = BLI_findlink(&scene->render_layers, scene->active_layer);
+	SceneLayer *sl = BKE_scene_layer_active(scene);
 
 	if (!BKE_scene_layer_remove(CTX_data_main(C), scene, sl)) {
 		return OPERATOR_CANCELLED;

source/blender/editors/space_view3d/view3d_draw_legacy.c

@@ -1453,7 +1453,7 @@ void ED_view3d_draw_depth(Scene *scene, ARegion *ar, View3D *v3d, bool alphaover
 	float glalphaclip = U.glalphaclip;
 	int obcenter_dia = U.obcenter_dia;
 	TODO_LAYER_CONTEXT; /* we should pass context, really */
-	SceneLayer *sl = BLI_findlink(&scene->render_layers, scene->active_layer);
+	SceneLayer *sl = BKE_scene_layer_active(scene);
 	/* no need for color when drawing depth buffer */
 	const short dflag_depth = DRAW_CONSTCOLOR;
 	/* temp set drawtype to solid */