Make the universe parts into small libraries.

pkg/compiler/lib/src/resolution/class_hierarchy.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.
 
 library dart2js.resolution.class_hierarchy;
 
 import '../compiler.dart' show
     Compiler;
 import '../dart_types.dart';
 import '../diagnostics/invariant.dart' show
     invariant;
 import '../diagnostics/messages.dart' show
     MessageKind;
 import '../elements/elements.dart';
 import '../elements/modelx.dart' show
     BaseClassElementX,
     ErroneousElementX,
     MixinApplicationElementX,
     SynthesizedConstructorElementX,
     TypeVariableElementX;
 import '../ordered_typeset.dart' show
     OrderedTypeSet,
     OrderedTypeSetBuilder;
 import '../tree/tree.dart';
 import '../util/util.dart' show
     Link,
     Setlet;
-import '../universe/universe.dart' show
-    CallStructure,
-    Selector;
+import '../universe/call_structure.dart' show
+    CallStructure;
 
 import 'enum_creator.dart';
 import 'members.dart' show
     lookupInScope;
 import 'registry.dart' show
     ResolutionRegistry;
 import 'resolution_common.dart' show
     CommonResolverVisitor,
     MappingVisitor;
 import 'scope.dart' show
@@ skipping 632 matching lines @@
     Identifier selector = node.selector.asIdentifier();
     var e = prefixElement.lookupLocalMember(selector.source);
     if (e == null || !e.impliesType) {
       error(node.selector, MessageKind.CANNOT_RESOLVE_TYPE,
             {'typeName': node.selector});
       return;
     }
     loadSupertype(e, node);
   }
 }