Make the universe parts into small libraries.

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 225 matching lines @@
     // For example, for the call-selector `call(x, y)` the renamed selector
     // for member `foo` would be `foo(x, y)`.
     Set<Selector> renamedCallSelectors =
         callSelectors.isEmpty ? emptySelectorSet : new Set<Selector>();
 
     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(
-          SelectorKind.CALL,
+      Selector renamedSelector = new Selector.call(
           member.memberName,
           selector.callStructure);
       renamedCallSelectors.add(renamedSelector);
 
       if (!renamedSelector.appliesUnnamed(member, compiler.world)) continue;
 
       if (untypedSelectors.add(renamedSelector)) {
         ParameterStubMethod stub =
             generateParameterStub(member, renamedSelector, selector);
         if (stub != null) {
@@ skipping 17 matching lines @@
             generateParameterStub(member, selector, null);
         if (stub != null) {
           stubs.add(stub);
         }
       }
     }
 
     return stubs;
   }
 }