fix android platform compile error

com.unity.uiwidgets/Runtime/services/keyboard.cs

 #endif
 
 #if UNITY_IOS || UNITY_ANDROID
-    /*class UIWidgetsTouchScreenKeyboardDelegate : AbstractUIWidgetsKeyboardDelegate {
+    class UIWidgetsTouchScreenKeyboardDelegate : AbstractUIWidgetsKeyboardDelegate {
 
         public override void show() {
             UIWidgetsTextInputShow();
 
         public override void clearClient() {
             UIWidgetsTextInputClearTextInputClient();
-        }*/
+        }
         
 #if UNITY_IOS
     /*
         
         [DllImport ("__Internal")]
         internal static extern void UIWidgetsTextInputClearTextInputClient();*/
+
+        internal static void UIWidgetsTextInputShow() {}
+        internal static void UIWidgetsTextInputHide() {}
+        internal static void UIWidgetsTextInputSetClient(int client, string configuration) {}
+        internal static void UIWidgetsTextInputSetTextInputEditingState(string jsonText) {}
+        internal static void UIWidgetsTextInputClearTextInputClient() {}
+        
 #elif UNITY_ANDROID
         internal static void UIWidgetsTextInputShow() {
             using (
             }
         }
 #endif
-    //}
+    }
 #endif
 }