GetBinding方法修改,在没有绑定设备时返回空迭代器而不是null

AxibugEmuOnline.Client/Assets/Script/AppMain/Manager/AppSettings/KeyMapperSetting/KeyMapperSetting.cs

@@ -5,7 +5,6 @@ using System;
 using System.Collections.Generic;
 using System.Linq;
 using UnityEngine;
-using static AxibugEmuOnline.Client.Settings.EmuCoreControllerKeyBinding<T>;
 
 namespace AxibugEmuOnline.Client.Settings
 {
@@ -319,7 +318,7 @@ namespace AxibugEmuOnline.Client.Settings
                     }
                 }
 
-                return null;
+                return Enumerable.Empty<InputDevice.InputControl>();
             }
 
             public bool AnyKeyDown()