Do not compile in removed bw compatibility.

src/Silk-Tests.js

@@ -7,10 +7,8 @@ define(["amber/boot"
 
 //>>excludeEnd("imports");
 ){"use strict";
-if(!$boot.nilAsReceiver)$boot.nilAsReceiver=$boot.nil;
 if(!("nilAsValue" in $boot))$boot.nilAsValue=$boot.nilAsReceiver;
 var $core=$boot.api,nil=$boot.nilAsValue,$nil=$boot.nilAsReceiver,$recv=$boot.asReceiver,$globals=$boot.globals;
-if(!$boot.nilAsClass)$boot.nilAsClass=$boot.dnu;
 $core.addPackage("Silk-Tests");
 $core.packages["Silk-Tests"].innerEval = function (expr) { return eval(expr); };
 $core.packages["Silk-Tests"].imports = ["amber/jquery/Wrappers-JQuery"];

src/Silk.js

@@ -1,8 +1,6 @@
 define(["amber/boot", "amber_core/Kernel-Collections", "amber_core/Kernel-Infrastructure", "amber_core/Kernel-Methods", "amber_core/Kernel-Objects", "domite/DOMite"], function($boot){"use strict";
-if(!$boot.nilAsReceiver)$boot.nilAsReceiver=$boot.nil;
 if(!("nilAsValue" in $boot))$boot.nilAsValue=$boot.nilAsReceiver;
 var $core=$boot.api,nil=$boot.nilAsValue,$nil=$boot.nilAsReceiver,$recv=$boot.asReceiver,$globals=$boot.globals;
-if(!$boot.nilAsClass)$boot.nilAsClass=$boot.dnu;
 $core.addPackage("Silk");
 $core.packages["Silk"].innerEval = function (expr) { return eval(expr); };
 $core.packages["Silk"].transport = {"type":"amd","amdNamespace":"silk"};