Bufixes: Event handling failed for old schema events.

src/Squidex.Domain.Apps.Write/Schemas/SchemaDomainObject.cs

@@ -55,7 +55,7 @@ namespace Squidex.Domain.Apps.Write.Schemas
 
         protected void On(SchemaCreated @event)
         {
-            totalFields += @event?.Fields.Count ?? 0;
+            totalFields += @event.Fields?.Count ?? 0;
 
             schema = SchemaEventDispatcher.Dispatch(@event, registry);
         }

src/Squidex/app-config/webpack.run.prod.js

@@ -97,7 +97,7 @@ module.exports = webpackMerge(runConfig, {
         new webpack.optimize.UglifyJsPlugin({
             beautify: false,
             mangle: {
-                screw_ie8: true
+                screw_ie8: true, keep_fnames: true
             },
             compress: {
                 screw_ie8: true, warnings: false