Handle NotSupportedException when accessing Assembly.Location

This is an improvement on I546aedbacb02b2a07352781865c5263304664909
which handles null Assembly locations but didn't handle the Location
property raising a NotSupportedException.

Fixes #362

Change-Id: I5c6aa3b48dd3af5d26b2187668bab114df5c8a1c

Author: Stewart Miles

source/VersionHandlerImpl/src/VersionHandlerImpl.cs

@@ -2349,14 +2349,17 @@ private static bool EnabledEditorDllsLoaded {
         get {
             var loadedAssemblyPaths = new HashSet<string>();
             foreach (var assembly in AppDomain.CurrentDomain.GetAssemblies()) {
-                if (String.IsNullOrEmpty(assembly.Location)) continue;
+                string location;
                 try {
-                    var path = Path.GetFullPath(assembly.Location);
-                    if (enabledEditorDlls.Contains(path)) {
-                        loadedAssemblyPaths.Add(path);
-                    }
+                    location = assembly.Location;
                 } catch (NotSupportedException) {
                     // Dynamic assemblies do not have a file location so ignore.
+                    continue;
+                }
+                if (String.IsNullOrEmpty(location)) continue;
+                var path = Path.GetFullPath(location);
+                if (enabledEditorDlls.Contains(path)) {
+                    loadedAssemblyPaths.Add(path);
                 }
             }
             return loadedAssemblyPaths.IsSupersetOf(enabledEditorDlls);