Pass ClassHierarchy instead of creating it.

pkg/front_end/lib/src/fasta/fasta.dart

 // Copyright (c) 2016, 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 fasta;
 
 import 'dart:async' show Future;
 
 import 'dart:convert' show JSON;
 
 import 'dart:io' show BytesBuilder, Directory, File, exitCode;
 
 import 'package:front_end/file_system.dart';
 import 'package:front_end/physical_file_system.dart';
 import 'package:front_end/src/fasta/kernel/utils.dart';
 import 'package:kernel/binary/ast_to_binary.dart'
     show LibraryFilteringBinaryPrinter;
 
+import 'package:kernel/class_hierarchy.dart' show ClassHierarchy;
+
 import 'package:kernel/core_types.dart' show CoreTypes;
 
 import 'package:kernel/kernel.dart' show Library, Program, loadProgramFromBytes;
 
 import 'package:kernel/target/targets.dart' show Target, TargetFlags, getTarget;
 
 import 'compiler_command_line.dart' show CompilerCommandLine;
 
 import 'compiler_context.dart' show CompilerContext;
 
@@ skipping 160 matching lines @@
     if (!await fileSystem.entityForUri(fileName).exists()) {
       return new CompilationResult.error(
           formatUnexpected(fileName, -1, "No such file."));
     }
     if (!await new Directory.fromUri(patchedSdk).exists()) {
       return new CompilationResult.error(
           formatUnexpected(patchedSdk, -1, "Patched sdk directory not found."));
     }
 
     CoreTypes coreTypes;
+    ClassHierarchy hierarchy;
     Program program;
     try {
       TranslateUri uriTranslator =
           await TranslateUri.parse(fileSystem, patchedSdk, packages: packages);
       final Ticker ticker = new Ticker(isVerbose: verbose);
       final DillTarget dillTarget =
           new DillTarget(ticker, uriTranslator, backendTarget);
       _appendDillForUri(dillTarget, patchedSdk.resolve('platform.dill'));
       final KernelTarget kernelTarget =
           new KernelTarget(fileSystem, dillTarget, uriTranslator, strongMode);
       kernelTarget.read(fileName);
       await dillTarget.buildOutlines();
       await kernelTarget.buildOutlines();
       coreTypes = kernelTarget.loader.coreTypes;
+      hierarchy = kernelTarget.loader.hierarchy;
       program = await kernelTarget.buildProgram();
       if (kernelTarget.errors.isNotEmpty) {
         return new CompilationResult.errors(kernelTarget.errors);
       }
     } on InputError catch (e) {
       return new CompilationResult.error(e.format());
     }
 
     if (program.mainMethod == null) {
       return new CompilationResult.error("No 'main' method found.");
     }
 
     // Perform target-specific transformations.
     Target target = getTarget("vm", new TargetFlags(strongMode: false));
-    target.performModularTransformations(coreTypes, program);
+    target.performModularTransformations(coreTypes, hierarchy, program);
     target.performGlobalTransformations(coreTypes, program);
 
     // Write the program to a list of bytes and return it.  Do not include
     // libraries that have a dart: import URI.
     //
     // TODO(kmillikin): This is intended to exclude platform libraries that are
     // included in the Kernel binary platform platform.dill.  It does not
     // necessarily exclude exactly the platform libraries.  Use a better
     // predicate that knows what is included in platform.dill.
     var sink = new ByteSink();
@@ skipping 67 matching lines @@
   final BytesBuilder builder = new BytesBuilder();
 
   void add(List<int> data) {
     builder.add(data);
   }
 
   void close() {
     // Nothing to do.
   }
 }