Coroutine 类型从IEnumerable为Iterator

demo/resource/default.res.json

@@ -1,7 +1,7 @@
 {
 	"groups": [
 		{
-			"keys": "bg_png,bgNorm_png,moon_png,orange_png,moonNorm_png,orangeNorm_png,tiledMap_json,orthogonal-outside_json,tilemap_json,plume_png",
+			"keys": "bg_png,bgNorm_png,moon_png,orange_png,moonNorm_png,orangeNorm_png,tiledMap_json,orthogonal-outside_json,tilemap_json,plume_png,cabbage_png",
 			"name": "preload"
 		},
 		{
@@ -116,6 +116,11 @@
 			"url": "preload/plume.png",
 			"type": "image",
 			"name": "plume_png"
+		},
+		{
+			"url": "preload/cabbage.png",
+			"type": "image",
+			"name": "cabbage_png"
 		}
 	]
 }