Remove dart2jslib.dart

tests/compiler/dart2js/deferred_custom_element_test.dart

 // Copyright (c) 2013, 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.
 
 // Test of the graph segmentation algorithm used by deferred loading
 // to determine which elements can be deferred and which libraries
 // much be included in the initial download (loaded eagerly).
 
 import 'package:async_helper/async_helper.dart';
-import 'package:compiler/src/dart2jslib.dart';
+import 'package:compiler/src/compiler.dart';
 import 'package:expect/expect.dart';
 import 'memory_compiler.dart';
 
 void main() {
   asyncTest(() async {
     CompilationResult result =
         await runCompiler(memorySourceFiles: MEMORY_SOURCE_FILES);
     Compiler compiler = result.compiler;
     var outputUnitForElement = compiler.deferredLoadTask.outputUnitForElement;
     var mainOutputUnit = compiler.deferredLoadTask.mainOutputUnit;
@@ skipping 22 matching lines @@
 import 'dart:html';
 var a = CustomType;
 
 class CustomType extends HtmlElement {
   factory CustomType() => null;
   CustomType.created() : super.created() ;
 }
 
 foo() {}
 """,};