Move dart2js from sdk/lib/_internal/compiler to pkg/compiler

sdk/lib/_internal/compiler/implementation/js_emitter/old_emitter/class_builder.dart

-// Copyright (c) 2013, 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.
-
-part of dart2js.js_emitter;
-
-/**
- * A data structure for collecting fragments of a class definition.
- */
-class ClassBuilder {
-  final List<jsAst.Property> properties = <jsAst.Property>[];
-  final List<String> fields = <String>[];
-
-  String superName;
-  String functionType;
-  List<jsAst.Node> fieldMetadata;
-
-  final Element element;
-  final Namer namer;
-
-  /// Set to true by user if class is indistinguishable from its superclass.
-  bool isTrivial = false;
-
-  ClassBuilder(this.element, this.namer);
-
-  // Has the same signature as [DefineStubFunction].
-  jsAst.Property addProperty(String name, jsAst.Expression value) {
-    jsAst.Property property = new jsAst.Property(js.string(name), value);
-    properties.add(property);
-    return property;
-  }
-
-  void addField(String field) {
-    fields.add(field);
-  }
-
-  jsAst.ObjectInitializer toObjectInitializer() {
-    StringBuffer buffer = new StringBuffer();
-    if (superName != null) {
-      buffer.write('$superName');
-      if (functionType != null) {
-        buffer.write(':$functionType');
-      }
-      buffer.write(';');
-    }
-    buffer.writeAll(fields, ',');
-    var classData = js.string('$buffer');
-    if (fieldMetadata != null) {
-      // If we need to store fieldMetadata, classData is turned into an array,
-      // and the field metadata is appended. So if classData is just a string,
-      // there is no field metadata.
-      classData =
-          new jsAst.ArrayInitializer.from([classData]..addAll(fieldMetadata));
-    }
-    var fieldsAndProperties =
-        [new jsAst.Property(js.string(namer.classDescriptorProperty),
-                            classData)]
-        ..addAll(properties);
-    return new jsAst.ObjectInitializer(fieldsAndProperties, isOneLiner: false);
-  }
-
-}