if def'd meshing demo properly to only compile on iOS

Assets/Common/Scripts/CenterScreenHelper.cs

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
-using UnityEngine.iOS;
 
 public class CenterScreenHelper : MonoBehaviour
 {

Assets/Meshing/Scripts/ClassificationPlacementManager.cs

 using DG.Tweening;
 using UnityEngine;
 using UnityEngine.EventSystems;
+#if UNITY_IOS
+#endif // UNITY_IOS
 using UnityEngine.XR.ARSubsystems;
 
 public class ClassificationPlacementManager : MonoBehaviour
 
     void Update()
     {
+#if UNITY_IOS
         if (m_ClassificationManager.currentClassification == ARMeshClassification.Table ||
             m_ClassificationManager.currentClassification == ARMeshClassification.Floor ||
             m_ClassificationManager.currentClassification == ARMeshClassification.Wall)
             m_WallUI.SetActive(false);
             m_TableUI.SetActive(false);
         }
+#endif
     }
 
     public void PlaceFloorObject(int indexToPlace)

Assets/Meshing/Scripts/MeshClassificationManager.cs

 using UnityEngine;
 using UnityEngine.XR;
 using UnityEngine.XR.ARFoundation;
+#if UNITY_IOS
+#endif // UNITY_IOS
 using UnityEngine.XR.ARSubsystems;
 
 public class MeshClassificationManager : MonoBehaviour
     RaycastHit m_Hit;
     TrackableId m_CurrentTrackableID;
     XRMeshSubsystem m_MeshSubsystem;
+#if UNITY_IOS
-
+#endif
+#if UNITY_IOS
-
+#endif
         m_MeshManager.meshesChanged += MeshManagerOnmeshesChanged;
     }
 
     {
         if (Physics.Raycast(m_MainCamera.ScreenPointToRay(CenterScreenHelper.Instance.GetCenterScreen()), out m_Hit))
         {
+#if UNITY_IOS
+#endif
+#if UNITY_IOS
         foreach (MeshFilter mesh in obj.added)
         {
             TrackableId trackableId = ExtractTrackableId(mesh.name);
 
             m_MeshDictionary.Remove(trackableId);
         }
+#endif
-
+    
+#if UNITY_IOS
     void SetCurrentClassification(TrackableId meshID, int triangleIndex)
     {
         Debug.Assert(m_MeshDictionary.ContainsKey(meshID), $"Mesh ID [{meshID}] does not exist in the dictionary");
         }
         return retVal;
     }
-
+#endif
     TrackableId ExtractTrackableId(string meshFilterName)
     {
         string[] nameSplit = meshFilterName.Split(' ');

ProjectSettings/EditorBuildSettings.asset

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+  m_Scenes:
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