Add wrapper for `Assembly.GetTypes()` which won't throw an exception

com.unity.shadergraph/Editor/Data/Nodes/MasterNode.cs

 using System.Collections.Generic;
 using System.Linq;
 using UnityEditor.Graphing;
+using UnityEditor.Graphing.Util;
 using UnityEngine;
 
 namespace UnityEditor.ShaderGraph
         {
             get { return typeof(T); }
         }
-        
+
         public IEnumerable<T> subShaders
         {
             get { return m_SubShaders; }
             base.UpdateNodeAfterDeserialization();
             foreach (var assembly in AppDomain.CurrentDomain.GetAssemblies())
             {
-                foreach (var type in assembly.GetTypes())
+                foreach (var type in assembly.GetTypesOrNothing())
                 {
                     var isValid = !type.IsAbstract && type.IsPublic && !type.IsGenericType && type.IsClass && typeof(T).IsAssignableFrom(type);
                     if (isValid && !subShaders.Any(s => s.GetType() == type))

com.unity.shadergraph/Editor/Data/Util/GraphUtil.cs

                 s_LegacyTypeRemapping = new Dictionary<SerializationHelper.TypeSerializationInfo, SerializationHelper.TypeSerializationInfo>();
                 foreach (var assembly in AppDomain.CurrentDomain.GetAssemblies())
                 {
-                    foreach (var type in assembly.GetTypes())
+                    foreach (var type in assembly.GetTypesOrNothing())
                     {
                         if (type.IsAbstract)
                             continue;

com.unity.shadergraph/Editor/Drawing/Blackboard/BlackboardField.cs

 using System.Linq;
 using System.Reflection;
 using UnityEditor.Experimental.UIElements.GraphView;
+using UnityEditor.Graphing.Util;
 using UnityEngine;
 using UnityEngine.Experimental.UIElements;
 
         public BlackboardField()
             : this(null, "", "") { }
 
-        static Type s_ContextualMenuManipulator = AppDomain.CurrentDomain.GetAssemblies().SelectMany(x => x.GetTypes()).FirstOrDefault(t => t.FullName == "UnityEngine.Experimental.UIElements.ContextualMenuManipulator");
+        static Type s_ContextualMenuManipulator = AppDomain.CurrentDomain.GetAssemblies().SelectMany(x => x.GetTypesOrNothing()).FirstOrDefault(t => t.FullName == "UnityEngine.Experimental.UIElements.ContextualMenuManipulator");
 
         public BlackboardField(Texture icon, string text, string typeText)
         {

com.unity.shadergraph/Editor/Drawing/Inspector/MasterPreviewView.cs

 using UnityEditor.Experimental.UIElements;
 using UnityEngine.Experimental.UIElements;
 using UnityEditor.Graphing;
+using UnityEditor.Graphing.Util;
 using UnityEngine.Experimental.UIElements.StyleSheets;
 using Object = UnityEngine.Object;
 
 
         List<string> m_DoNotShowPrimitives = new List<string>( new string[] {PrimitiveType.Plane.ToString()});
 
-        static Type s_ContextualMenuManipulator = AppDomain.CurrentDomain.GetAssemblies().SelectMany(x => x.GetTypes()).FirstOrDefault(t => t.FullName == "UnityEngine.Experimental.UIElements.ContextualMenuManipulator");
-        static Type s_ObjectSelector = AppDomain.CurrentDomain.GetAssemblies().SelectMany(x => x.GetTypes()).FirstOrDefault(t => t.FullName == "UnityEditor.ObjectSelector");
+        static Type s_ContextualMenuManipulator = AppDomain.CurrentDomain.GetAssemblies().SelectMany(x => x.GetTypesOrNothing()).FirstOrDefault(t => t.FullName == "UnityEngine.Experimental.UIElements.ContextualMenuManipulator");
+        static Type s_ObjectSelector = AppDomain.CurrentDomain.GetAssemblies().SelectMany(x => x.GetTypesOrNothing()).FirstOrDefault(t => t.FullName == "UnityEditor.ObjectSelector");
 
         public MasterPreviewView(string assetName, PreviewManager previewManager, AbstractMaterialGraph graph)
         {

com.unity.shadergraph/Editor/Drawing/SearchWindowProvider.cs

 using UnityEditor.Experimental.UIElements;
 using UnityEditor.Experimental.UIElements.GraphView;
 using UnityEditor.Graphing;
+using UnityEditor.Graphing.Util;
 using UnityEngine;
 using UnityEngine.Experimental.UIElements;
 
             var nodeEntries = new List<NodeEntry>();
             foreach (var assembly in AppDomain.CurrentDomain.GetAssemblies())
             {
-                foreach (var type in assembly.GetTypes())
+                foreach (var type in assembly.GetTypesOrNothing())
                 {
                     if (type.IsClass && !type.IsAbstract && (type.IsSubclassOf(typeof(AbstractMaterialNode))) && type != typeof(PropertyNode))
                     {

com.unity.shadergraph/Editor/Util/UIUtilities.cs

 using System;
 using System.Collections.Generic;
 using System.Linq;
+using System.Reflection;
 
 namespace UnityEditor.Graphing.Util
 {
         public static IEnumerable<T> ToEnumerable<T>(this T item)
         {
             yield return item;
+        }
+
+        public static IEnumerable<Type> GetTypesOrNothing(this Assembly assembly)
+        {
+            try
+            {
+                return assembly.GetTypes();
+            }
+            catch
+            {
+                return Enumerable.Empty<Type>();
+            }
         }
     }
 }