Don't recreate CoreTypes in transformers. Pass it in.

pkg/kernel/lib/transformations/method_call.dart

 // Copyright (c) 2017, 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 kernel.transformations.method_call;
 
 import 'dart:math' as math;
 
 import '../ast.dart';
 import '../class_hierarchy.dart';
@@ skipping 35 matching lines @@
 /// }
 ///
 /// class B extends A {
 ///   foo(required1) => print("Hello from class B");
 /// }
 ///
 /// main() {
 ///   var b = new B();
 ///   b.foo(499, named1: 88);
 /// }
-Program transformProgram(Program program, [debug = false]) {
-  new MethodCallTransformer(debug).visitProgram(program);
+Program transformProgram(CoreTypes coreTypes, Program program,
+    [debug = false]) {
+  new MethodCallTransformer(coreTypes, debug).visitProgram(program);
   return program;
 }
 
 class MethodCallTransformer extends Transformer {
+  final CoreTypes coreTypes;
+
   /// Keep track of "visited" procedures and constructors to not visit already
   /// visited stuff, nor visit newly created stubs.
   Set<Member> _visited = new Set<Member>();
 
   /// Some things currently cannot be rewritten. Calls to methods called "call"
   /// (because invoking tear-offs and closures and whatnot becomes .call)
   /// as well as clashes with field names as a field can contain a function
   /// and one can then do a clazz.fieldName(...).
   Set<String> blacklistedSelectors = new Set<String>.from(["call"]);
 
@@ skipping 26 matching lines @@
   /// For non-static method transformations:
   /// Maps a procedure to the mapping of argument signature to procedure stub.
   Map<Procedure, Map<String, Procedure>> _superProcedureCalls = {};
 
   /// Whether in debug mode, i.e. if we can insert extra print statements for
   /// debugging purposes.
   bool _debug;
 
   /// For noSuchMethod calls.
   ClassHierarchy hierarchy;
-  CoreTypes coreTypes;
   Constructor _invocationMirrorConstructor; // cached
   Procedure _listFrom; // cached
 
-  MethodCallTransformer(this._debug);
+  MethodCallTransformer(this.coreTypes, this._debug);
 
   @override
   TreeNode visitProgram(Program node) {
     hierarchy = new ClassHierarchy(node);
-    coreTypes = new CoreTypes(node);
 
     // First move body of all procedures that takes optional positional or named
     // parameters and record which non-static procedure names have optional
     // positional arguments.
     // Do the same for constructors. Then also rewrite constructor initializers
     // using LocalInitializer and sort named arguments in those initializers
     for (final library in node.libraries) {
       for (final procedure in new List<Procedure>.from(library.procedures)) {
         _moveAndTransformProcedure(procedure);
       }
@@ skipping 1178 matching lines @@
     return printStackTrace;
   }
 }
 
 class _Pair<K, V> {
   final K key;
   final V value;
 
   _Pair(this.key, this.value);
 }