Support compilation of Hello World

pkg/compiler/lib/src/constants/constant_system.dart

 // Copyright (c) 2012, 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.constant_system;
 
 import '../dart_types.dart';
 import '../compiler.dart' show Compiler;
 import '../resolution/operators.dart';
 import '../tree/tree.dart' show DartString;
@@ skipping 50 matching lines @@
   ConstantValue createDouble(double d);
   ConstantValue createString(DartString string);
   ConstantValue createBool(bool value);
   ConstantValue createNull();
   ConstantValue createList(InterfaceType type, List<ConstantValue> values);
   // TODO(johnniwinther): Remove the need for [compiler].
   ConstantValue createMap(Compiler compiler, InterfaceType type,
       List<ConstantValue> keys, List<ConstantValue> values);
   // TODO(johnniwinther): Remove the need for [compiler].
   ConstantValue createType(Compiler compiler, DartType type);
+  // TODO(johnniwinther): Remove the need for [compiler].
+  ConstantValue createSymbol(Compiler compiler, String text);
 
   // We need to special case the subtype check for JavaScript constant
   // system because an int is a double at runtime.
   bool isSubtype(DartTypes types, DartType s, DartType t);
 
   /** Returns true if the [constant] is an integer at runtime. */
   bool isInt(ConstantValue constant);
   /** Returns true if the [constant] is a double at runtime. */
   bool isDouble(ConstantValue constant);
   /** Returns true if the [constant] is a string at runtime. */
@@ skipping 54 matching lines @@
         return greaterEqual;
       case BinaryOperatorKind.EQ:
         return equal;
       case BinaryOperatorKind.IF_NULL:
         return ifNull;
       default:
         return null;
     }
   }
 }