Split up TypeInferrer class.

pkg/front_end/lib/src/fasta/kernel/body_builder.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.body_builder;
 
 import '../fasta_codes.dart'
     show FastaMessage, codeExpectedButGot, codeExpectedFunctionBody;
 
 import '../parser/parser.dart' show FormalParameterType, optional;
 
 import '../parser/identifier_context.dart' show IdentifierContext;
 
 import 'package:front_end/src/fasta/builder/ast_factory.dart' show AstFactory;
 
 import 'package:front_end/src/fasta/kernel/kernel_shadow_ast.dart'
     show KernelField, KernelVariableDeclaration;
 
+import 'package:front_end/src/fasta/type_inference/type_inference_engine.dart'
+    show FieldNode;
+
 import 'package:front_end/src/fasta/type_inference/type_inferrer.dart'
-    show FieldNode, TypeInferrer;
+    show TypeInferrer;
 
 import 'package:kernel/ast.dart';
 
 import 'package:kernel/clone.dart' show CloneVisitor;
 
 import 'package:kernel/transformations/flags.dart' show TransformerFlag;
 
 import 'package:kernel/class_hierarchy.dart' show ClassHierarchy;
 
 import 'package:kernel/core_types.dart' show CoreTypes;
@@ skipping 414 matching lines @@
 
   @override
   void endInitializers(int count, Token beginToken, Token endToken) {
     debugEvent("Initializers");
   }
 
   @override
   void finishFunction(
       FormalParameters formals, AsyncMarker asyncModifier, Statement body) {
     debugEvent("finishFunction");
-    _typeInferrer.inferBody(body, uri);
+    _typeInferrer.inferStatement(body);
     KernelFunctionBuilder builder = member;
     builder.body = body;
     if (formals?.optional != null) {
       Iterator<FormalParameterBuilder> formalBuilders =
           builder.formals.skip(formals.required.length).iterator;
       for (VariableDeclaration parameter in formals.optional.formals) {
         bool hasMore = formalBuilders.moveNext();
         assert(hasMore);
         VariableDeclaration realParameter = formalBuilders.current.target;
         Expression initializer = parameter.initializer ?? new NullLiteral();
@@ skipping 2625 matching lines @@
   } else if (node is PrefixBuilder) {
     return node.name;
   } else if (node is ThisAccessor) {
     return node.isSuper ? "super" : "this";
   } else if (node is FastaAccessor) {
     return node.plainNameForRead;
   } else {
     return internalError("Unhandled: ${node.runtimeType}");
   }
 }