When reordering constructor initializers, use correct types for temp vars.

pkg/front_end/lib/src/fasta/type_inference/type_inference_engine.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.md file.
 
 import 'package:front_end/src/base/instrumentation.dart';
 import 'package:front_end/src/dependency_walker.dart' as dependencyWalker;
 import 'package:front_end/src/fasta/problems.dart' show unhandled;
 import 'package:front_end/src/fasta/kernel/kernel_shadow_ast.dart';
 import 'package:front_end/src/fasta/type_inference/type_inference_listener.dart';
 import 'package:front_end/src/fasta/type_inference/type_inferrer.dart';
@@ skipping 122 matching lines @@
 abstract class TypeInferenceEngine {
   ClassHierarchy get classHierarchy;
 
   CoreTypes get coreTypes;
 
   /// Creates a type inferrer for use inside of a method body declared in a file
   /// with the given [uri].
   TypeInferrer createLocalTypeInferrer(
       Uri uri, TypeInferenceListener listener, InterfaceType thisType);
 
+  /// Creates a disabled type inferrer (intended for debugging and profiling
+  /// only).
+  TypeInferrer createDisabledTypeInferrer();
+
   /// Creates a [TypeInferrer] object which is ready to perform type inference
   /// on the given [field].
   TypeInferrer createTopLevelTypeInferrer(TypeInferenceListener listener,
       InterfaceType thisType, KernelMember member);
 
   /// Performs the second phase of top level initializer inference, which is to
   /// visit all accessors and top level variables that were passed to
   /// [recordAccessor] in topologically-sorted order and assign their types.
   void finishTopLevel();
 
@@ skipping 487 matching lines @@
   }
 
   @override
   void evaluateScc(List<AccessorNode> scc) {
     // Mark every accessor as part of a circularity.
     for (var f in scc) {
       f._typeInferenceEngine.inferAccessorCircular(f);
     }
   }
 }