Remove ConstantExpression.value

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

 // Copyright (c) 2015, 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;
 
 class ParameterStubGenerator {
   static final Set<Selector> emptySelectorSet = new Set<Selector>();
 
   final Namer namer;
@@ skipping 82 matching lines @@
       } else {
         int index = names.indexOf(element.name);
         if (index != -1) {
           indexOfLastOptionalArgumentInParameters = count;
           // The order of the named arguments is not the same as the
           // one in the real method (which is in Dart source order).
           argumentsBuffer[count] = js('#', jsName);
           parametersBuffer[optionalParameterStart + index] =
               new jsAst.Parameter(jsName);
         } else {
-          ConstantExpression constant = handler.getConstantForVariable(element);
-          if (constant == null) {
+          ConstantValue value = handler.getConstantValueForVariable(element);
+          if (value == null) {
             argumentsBuffer[count] =
                 emitter.constantReference(new NullConstantValue());
           } else {
-            ConstantValue value = constant.value;
             if (!value.isNull) {
               // If the value is the null constant, we should not pass it
               // down to the native method.
               indexOfLastOptionalArgumentInParameters = count;
             }
             argumentsBuffer[count] = emitter.constantReference(value);
           }
         }
       }
       count++;
@@ skipping 154 matching lines @@
             generateParameterStub(member, selector, null);
         if (stub != null) {
           stubs.add(stub);
         }
       }
     }
 
     return stubs;
   }
 }