Rename Constant to ConstantValue and ConstExp to ConstantExpression.

sdk/lib/_internal/compiler/implementation/cps_ir/optimizers.dart

Index: sdk/lib/_internal/compiler/implementation/cps_ir/optimizers.dart
diff --git a/sdk/lib/_internal/compiler/implementation/cps_ir/optimizers.dart b/sdk/lib/_internal/compiler/implementation/cps_ir/optimizers.dart
index 276009feaa544b2cd2b868b39a516c514debae2d..6a23019f7e5a4ca0a745c2625ce1baf379ae3f31 100644
--- a/sdk/lib/_internal/compiler/implementation/cps_ir/optimizers.dart
+++ b/sdk/lib/_internal/compiler/implementation/cps_ir/optimizers.dart
@@ -4,8 +4,10 @@
 
 library dart2js.optimizers;
 
-import '../constants/expressions.dart' show ConstExp, PrimitiveConstExp;
-import '../constants/values.dart' as values;
+import '../constants/expressions.dart' show
+    ConstantExpression,
+    PrimitiveConstantExpression;
+import '../constants/values.dart';
 import '../dart_types.dart' as types;
 import '../dart2jslib.dart' as dart2js;
 import '../elements/elements.dart' show ClassElement;