Merge pull request #953 from Unity-Technologies/domain-reload-optim

Faster domain reload

ScriptableRenderPipeline/Core/CoreRP/CoreUtils.cs

-using System;
+using System;
 using System.Collections.Generic;
 using System.Linq;
 using UnityEngine.Rendering;
             }
         }
 
+        static IEnumerable<Type> m_AssemblyTypes;
+
-            return AppDomain.CurrentDomain.GetAssemblies()
-                .SelectMany(t =>
-                {
-                    // Ugly hack to handle mis-versioned dlls
-                    var innerTypes = new Type[0];
-                    try
+            if (m_AssemblyTypes == null)
+            {
+                m_AssemblyTypes = AppDomain.CurrentDomain.GetAssemblies()
+                    .SelectMany(t =>
-                        innerTypes = t.GetTypes();
-                    }
-                    catch { }
-                    return innerTypes;
-                });
+                        // Ugly hack to handle mis-versioned dlls
+                        var innerTypes = new Type[0];
+                        try
+                        {
+                            innerTypes = t.GetTypes();
+                        }
+                        catch { }
+                        return innerTypes;
+                    });
+            }
+
+            return m_AssemblyTypes;
         }
 
         public static void Destroy(params UnityObject[] objs)