Hide reference to ProceduralMaterial. (#663)

* Hide reference to ProceduralMaterial.

* remove class obsolete for the past 8 years

* changelog

---------

Co-authored-by: Thomas Lopez <thomas.lopez@unity3d.com>
Co-authored-by: Thomas Lopez <66317117+lopezt-unity@users.noreply.github.com>

Author: Thomasch-unity3d

CHANGELOG.md

@@ -8,6 +8,8 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 ## Unreleased
 
 ### Changes
+
+- [UUM-138539] Removed the pb_ObjectArray file that was deprecated 8 years ago and is not used amymore.
 - [UUM-138960] Removed a large utility dictionary to reduce binary size and runtime memory overhead. 
 
 ### Fixed

Editor/EditorCore/MaterialEditor.cs

@@ -173,24 +173,8 @@ public static MaterialPalette CurrentPalette
                     if (s_CurrentPalette != null)
                         return s_CurrentPalette;
 
-                    // If no existing pb_MaterialPalette objects in project:
-                    // - create a new one
-                    // - check for the older pb_ObjectArray and copy data to new default
+                    // If no existing pb_MaterialPalette objects in project create a new one
                     s_CurrentPalette = FileUtility.LoadRequired<MaterialPalette>(s_MaterialPalettePath);
-
-                    string[] m_LegacyMaterialArrays = AssetDatabase.FindAssets("t:pb_ObjectArray");
-
-                    for (int i = 0; m_LegacyMaterialArrays != null && i < m_LegacyMaterialArrays.Length; i++)
-                    {
-                        pb_ObjectArray poa = AssetDatabase.LoadAssetAtPath<pb_ObjectArray>(AssetDatabase.GUIDToAssetPath(m_LegacyMaterialArrays[i]));
-
-                        // Make sure there's actually something worth copying
-                        if (poa != null && poa.array != null && poa.array.Any(x => x != null && x is Material))
-                        {
-                            s_CurrentPalette.array = poa.GetArray<Material>();
-                            break;
-                        }
-                    }
                 }
                 return s_CurrentPalette;
             }