Introduce OpenWorld.

pkg/compiler/lib/src/js_emitter/parameter_stub_generator.dart

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of dart2js.js_emitter;
 
 class ParameterStubGenerator {
   static final Set<Selector> emptySelectorSet = new Set<Selector>();
 
   final Namer namer;
@@ skipping 230 matching lines @@
 
     Set<Selector> untypedSelectors = new Set<Selector>();
 
     // Start with the callSelectors since they imply the generation of the
     // non-call version.
     for (Selector selector in callSelectors.keys) {
       Selector renamedSelector =
           new Selector.call(member.memberName, selector.callStructure);
       renamedCallSelectors.add(renamedSelector);
 
-      if (!renamedSelector.appliesUnnamed(member, compiler.closedWorld))
+      if (!renamedSelector.appliesUnnamed(member, backend))
         continue;
 
       if (untypedSelectors.add(renamedSelector)) {
         ParameterStubMethod stub =
             generateParameterStub(member, renamedSelector, selector);
         if (stub != null) {
           stubs.add(stub);
         }
       }
     }
 
     // Now run through the actual member selectors (eg. `foo$2(x, y)` and not
     // `call$2(x, y)`. Some of them have already been generated because of the
     // call-selectors (and they are in the renamedCallSelectors set.
     for (Selector selector in selectors.keys) {
       if (renamedCallSelectors.contains(selector)) continue;
-      if (!selector.appliesUnnamed(member, compiler.closedWorld)) continue;
+      if (!selector.appliesUnnamed(member, backend)) continue;
       if (!selectors[selector]
           .applies(member, selector, compiler.closedWorld)) {
         continue;
       }
 
       if (untypedSelectors.add(selector)) {
         ParameterStubMethod stub =
             generateParameterStub(member, selector, null);
         if (stub != null) {
           stubs.add(stub);
         }
       }
     }
 
     return stubs;
   }
 }