fix sorting storage does not change original difflayer

Author: dean65

core/blockchain.go

@@ -521,13 +521,13 @@ func (bc *BlockChain) cacheDiffLayer(diffLayer *types.DiffLayer, diffLayerCh cha
 	sort.SliceStable(diffLayer.Storages, func(i, j int) bool {
 		return diffLayer.Storages[i].Account.Hex() < diffLayer.Storages[j].Account.Hex()
 	})
-	for _, storage := range diffLayer.Storages {
+	for index := range diffLayer.Storages {
 		// Sort keys and vals by key.
-		sort.SliceStable(storage.Keys, func(i, j int) bool {
-			return storage.Keys[i] < storage.Keys[j]
+		sort.SliceStable(diffLayer.Storages[index].Keys, func(i, j int) bool {
+			return diffLayer.Storages[index].Keys[i] < diffLayer.Storages[index].Keys[j]
 		})
-		sort.SliceStable(storage.Vals, func(i, j int) bool {
-			return storage.Keys[i] < storage.Keys[j]
+		sort.SliceStable(diffLayer.Storages[index].Vals, func(i, j int) bool {
+			return diffLayer.Storages[index].Keys[i] < diffLayer.Storages[index].Keys[j]
 		})
 	}