Extract DartTypeVisitor and subclasses from resolution_types.

pkg/compiler/lib/src/js_emitter/program_builder/program_builder.dart

 // Copyright (c) 2014, 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 dart2js.js_emitter.program_builder;
 
 import '../../closure.dart' show ClosureTask, ClosureFieldElement;
 import '../../common.dart';
 import '../../common/names.dart' show Names, Selectors;
 import '../../constants/values.dart'
     show ConstantValue, InterceptorConstantValue;
 import '../../common_elements.dart' show CommonElements;
-import '../../elements/resolution_types.dart'
-    show ResolutionDartType, ResolutionFunctionType, ResolutionTypedefType;
 import '../../deferred_load.dart' show DeferredLoadTask, OutputUnit;
 import '../../elements/elements.dart'
     show
         ClassElement,
         Element,
         Elements,
         FieldElement,
         FunctionElement,
         FunctionSignature,
         GetterElement,
         LibraryElement,
         MemberElement,
         MethodElement,
         ParameterElement,
         TypedefElement,
         VariableElement;
 import '../../elements/entities.dart';
-import '../../elements/resolution_types.dart' show Types;
+import '../../elements/resolution_types.dart'
+    show
+        DartTypes,
+        ResolutionDartType,
+        ResolutionFunctionType,
+        ResolutionTypedefType;
 import '../../elements/types.dart' show DartType;
 import '../../js/js.dart' as js;
 import '../../js_backend/backend.dart'
     show
         RuntimeTypesChecks,
         RuntimeTypesNeed,
         RuntimeTypesEncoder,
         RuntimeTypesSubstitutions,
         SuperMemberData;
 import '../../js_backend/backend_usage.dart';
@@ skipping 26 matching lines @@
 
 part 'collector.dart';
 part 'field_visitor.dart';
 part 'registry.dart';
 
 /// Builds a self-contained representation of the program that can then be
 /// emitted more easily by the individual emitters.
 class ProgramBuilder {
   final CompilerOptions _options;
   final CommonElements _commonElements;
-  final Types _types;
+  final DartTypes _types;
   final DeferredLoadTask _deferredLoadTask;
   final ClosureTask _closureToClassMapper;
   final CodegenWorldBuilder _worldBuilder;
   final NativeCodegenEnqueuer _nativeCodegenEnqueuer;
   final BackendUsage _backendUsage;
   final JavaScriptConstantCompiler _constantHandler;
   final NativeData _nativeData;
   final RuntimeTypesNeed _rtiNeed;
   final MirrorsData _mirrorsData;
   final InterceptorData _interceptorData;
@@ skipping 1005 matching lines @@
       Constant constant = new Constant(name, holder, constantValue);
       _constants[constantValue] = constant;
     }
   }
 
   Holder _registerStaticStateHolder() {
     return _registry.registerHolder(_namer.staticStateHolder,
         isStaticStateHolder: true);
   }
 }