Handle int/double literals in inference

pkg/compiler/lib/src/inferrer/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.
 
 library simple_types_inferrer;
 
 import '../closure.dart' show ClosureRepresentationInfo;
 import '../common.dart';
 import '../common/names.dart' show Identifiers, Selectors;
 import '../compiler.dart' show Compiler;
@@ skipping 201 matching lines @@
   TypeInformation visitStringJuxtaposition(ast.StringJuxtaposition node) {
     node.visitChildren(this);
     return types.stringType;
   }
 
   TypeInformation visitLiteralBool(ast.LiteralBool node) {
     return types.boolLiteralType(node.value);
   }
 
   TypeInformation visitLiteralDouble(ast.LiteralDouble node) {
-    ConstantSystem constantSystem = compiler.backend.constantSystem;
+    ConstantSystem constantSystem = closedWorld.constantSystem;
     // The JavaScript backend may turn this literal into an integer at
     // runtime.
     return types.getConcreteTypeFor(
         computeTypeMask(closedWorld, constantSystem.createDouble(node.value)));
   }
 
   TypeInformation visitLiteralInt(ast.LiteralInt node) {
-    ConstantSystem constantSystem = compiler.backend.constantSystem;
+    ConstantSystem constantSystem = closedWorld.constantSystem;
     // The JavaScript backend may turn this literal into a double at
     // runtime.
     return types.getConcreteTypeFor(
         computeTypeMask(closedWorld, constantSystem.createInt(node.value)));
   }
 
   TypeInformation visitLiteralNull(ast.LiteralNull node) {
     return types.nullType;
   }
 
@@ skipping 2752 matching lines @@
         node,
         iteratorSelector,
         iteratorMask,
         expressionType,
         new ArgumentsTypes.empty());
 
     return handleForInLoop(node, iteratorType, currentSelector, currentMask,
         moveNextSelector, moveNextMask);
   }
 }