Make the universe parts into small libraries.

tests/compiler/dart2js/cpa_inference_test.dart

 // Copyright (c) 2012, 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.
 
 import 'dart:async';
 import "package:expect/expect.dart";
 import "package:async_helper/async_helper.dart";
 import 'package:compiler/src/types/types.dart';
 import 'package:compiler/src/inferrer/concrete_types_inferrer.dart';
-import 'package:compiler/src/universe/universe.dart' show
-    CallStructure,
+import 'package:compiler/src/universe/call_structure.dart' show
+    CallStructure;
+import 'package:compiler/src/universe/selector.dart' show
     Selector;
 
 import "compiler_helper.dart";
 import "type_mask_test_helper.dart";
 
 /**
  * Finds the node corresponding to the last occurence of the substring
  * [: identifier; :] in the program represented by the visited AST.
  */
 class VariableFinderVisitor extends Visitor {
@@ skipping 2128 matching lines @@
     testClosures10,
     testClosures11,
     testClosures12,
     testRefinement,
     testDefaultArguments,
     testSuperConstructorCall,
     testSuperConstructorCall2,
     testSuperConstructorCall3,
   ], (f) => f()));
 }