Rename Constant to ConstantValue and ConstExp to ConstantExpression.

sdk/lib/_internal/compiler/implementation/native/behavior.dart

Index: sdk/lib/_internal/compiler/implementation/native/behavior.dart
diff --git a/sdk/lib/_internal/compiler/implementation/native/behavior.dart b/sdk/lib/_internal/compiler/implementation/native/behavior.dart
index 6733375dfa5940d5e50eac0ffa921301e08b4c2b..328f42594b20560f745bf85ad738c345dfaf97b0 100644
--- a/sdk/lib/_internal/compiler/implementation/native/behavior.dart
+++ b/sdk/lib/_internal/compiler/implementation/native/behavior.dart
@@ -352,19 +352,19 @@ class NativeBehavior {
          !link.isEmpty;
          link = link.tail) {
       MetadataAnnotation annotation = link.head.ensureResolved(compiler);
-      Constant value = annotation.constant.value;
+      ConstantValue value = annotation.constant.value;
       if (!value.isConstructedObject) continue;
-      ConstructedConstant constructedObject = value;
+      ConstructedConstantValue constructedObject = value;
       if (constructedObject.type.element != annotationClass) continue;
 
-      List<Constant> fields = constructedObject.fields;
+      List<ConstantValue> fields = constructedObject.fields;
       // TODO(sra): Better validation of the constant.
       if (fields.length != 1 || !fields[0].isString) {
         PartialMetadataAnnotation partial = annotation;
         compiler.internalError(annotation,
             'Annotations needs one string: ${partial.parseNode(compiler)}');
       }
-      StringConstant specStringConstant = fields[0];
+      StringConstantValue specStringConstant = fields[0];
       String specString = specStringConstant.toDartString().slowToString();
       for (final typeString in specString.split('|')) {
         var type = _parseType(typeString, compiler, lookup, annotation);