Handle the newly refactored minecarts.

src/main/java/org/bukkit/craftbukkit/entity/CraftMinecartChest.java

@@ -0,0 +1,32 @@
+package org.bukkit.craftbukkit.entity;
+
+import net.minecraft.server.EntityMinecartChest;
+
+import org.bukkit.craftbukkit.CraftServer;
+import org.bukkit.craftbukkit.inventory.CraftInventory;
+import org.bukkit.entity.EntityType;
+import org.bukkit.entity.StorageMinecart;
+import org.bukkit.inventory.Inventory;
+
+@SuppressWarnings("deprecation")
+public class CraftMinecartChest extends CraftMinecart implements StorageMinecart {
+    private final CraftInventory inventory;
+
+    public CraftMinecartChest(CraftServer server, EntityMinecartChest entity) {
+        super(server, entity);
+        inventory = new CraftInventory(entity);
+    }
+
+    public Inventory getInventory() {
+        return inventory;
+    }
+
+    @Override
+    public String toString() {
+        return "CraftMinecartChest{" + "inventory=" + inventory + '}';
+    }
+
+    public EntityType getType() {
+        return EntityType.MINECART_CHEST;
+    }
+}