Fix T41630: Edge Split Modifier don't work anymore when a Array Modifier is after the Edge Split Modifier added.

Dirty normals flag has to be passed to new dm...

source/blender/modifiers/intern/MOD_array.c

@@ -690,6 +690,13 @@ static DerivedMesh *arrayModifier_doArray(
 	}
 	/* done capping */
 
+	/* In case org dm has dirty normals, or we made some merging, mark normals as dirty in new dm!
+	 * TODO: we may need to set other dirty flags as well?
+	 */
+	if ((dm->dirty & DM_DIRTY_NORMALS) || full_doubles_map) {
+		result->dirty |= DM_DIRTY_NORMALS;
+	}
+
 	/* Handle merging */
 	tot_doubles = 0;
 	if (full_doubles_map) {