merge mode in HDProbe

com.unity.render-pipelines.high-definition/HDRP/Lighting/Reflection/HDAdditionalReflectionData.cs

 using UnityEngine.Serialization;
 using UnityEngine.Experimental.Rendering.HDPipeline;
-using System;
+using UnityEngine.Rendering;
 
 namespace UnityEngine.Experimental.Rendering
 {
         [HideInInspector]
-        const int currentVersion = 1;
+        const int currentVersion = 2;
+        ReflectionProbe m_LegacyProbe;
+        ReflectionProbe legacyProbe { get { return m_LegacyProbe ?? (m_LegacyProbe = GetComponent<ReflectionProbe>()); } }
+
         public ShapeType influenceShape;
         public float influenceSphereRadius = 3.0f;
         public float sphereReprojectionVolumeRadius = 1.0f;
         [SerializeField] private float editorSimplifiedModeBlendNormalDistance;
         [SerializeField] private bool editorAdvancedModeEnabled;
 
+        bool needMigrateToHDProbeChild = false;
+
         public Vector3 boxBlendCenterOffset { get { return (blendDistanceNegative - blendDistancePositive) * 0.5f; } }
         public Vector3 boxBlendSizeOffset { get { return -(blendDistancePositive + blendDistanceNegative); } }
         public Vector3 boxBlendNormalCenterOffset { get { return (blendNormalDistanceNegative - blendNormalDistancePositive) * 0.5f; } }
             if (m_Version != currentVersion)
             {
                 // Add here data migration code
-                m_Version = currentVersion;
+                if (m_Version < 2)
+                {
+                    needMigrateToHDProbeChild = true;
+                }
+                else
+                {
+                    m_Version = currentVersion;
+                }
+            }
+        }
+
+        private void OnEnable()
+        {
+            if (needMigrateToHDProbeChild)
+                MigrateToHDProbeChild();
+        }
+
+        void MigrateToHDProbeChild()
+        {
+            mode = legacyProbe.mode;
+            m_Version = 2;
+            OnAfterDeserialize();   //continue migrating if needed
+        }
+
+        public override ReflectionProbeMode mode
+        {
+            set
+            {
+                base.mode = value;
+                legacyProbe.mode = value; //ensure compatibility till we capture without the legacy component
             }
         }
     }

com.unity.render-pipelines.high-definition/HDRP/Lighting/Reflection/HDProbe.cs

 using UnityEngine;
+using UnityEngine.Rendering;
 using UnityEngine.Serialization;
 
 namespace UnityEngine.Experimental.Rendering.HDPipeline
         [Range(0.0f, 1.0f)]
         float m_Weight = 1.0f;
 
+        [SerializeField]
+        ReflectionProbeMode m_Mode = ReflectionProbeMode.Baked;
+
+        public virtual ReflectionProbeMode mode
+        {
+            get { return m_Mode; }
+            set { m_Mode = value; }
+        }
     }
 }

com.unity.render-pipelines.high-definition/HDRP/Lighting/Reflection/PlanarReflectionProbe.cs

         [SerializeField]
         Vector3 m_CaptureLocalPosition;
         [SerializeField]
-        ReflectionProbeMode m_Mode = ReflectionProbeMode.Baked;
-        [SerializeField]
         ReflectionProbeRefreshMode m_RefreshMode = ReflectionProbeRefreshMode.OnAwake;
         [SerializeField]
         Texture m_CustomTexture;
         {
             get
             {
-                switch (m_Mode)
+                switch (mode)
                 {
                     default:
                     case ReflectionProbeMode.Baked:
         }
         public Bounds bounds { get { return m_InfluenceVolume.GetBoundsAt(transform); } }
         public Vector3 captureLocalPosition { get { return m_CaptureLocalPosition; } set { m_CaptureLocalPosition = value; } }
-        public ReflectionProbeMode mode { get { return m_Mode; } }
         public Matrix4x4 influenceToWorld
         {
             get