Check enums in switch cases.

pkg/compiler/lib/src/resolution/enum_creator.dart

Index: pkg/compiler/lib/src/resolution/enum_creator.dart
diff --git a/pkg/compiler/lib/src/resolution/enum_creator.dart b/pkg/compiler/lib/src/resolution/enum_creator.dart
index fcc179682edea72902cb83327c827a339d076224..8d1a875172dc0aa7f6a020762c53f8a8376e6470 100644
--- a/pkg/compiler/lib/src/resolution/enum_creator.dart
+++ b/pkg/compiler/lib/src/resolution/enum_creator.dart
@@ -198,6 +198,7 @@ class EnumCreator {
     constructor.functionSignatureCache = constructorSignature;
     enumClass.addMember(constructor, compiler);
 
+    List<FieldElement> enumValues = <FieldElement>[];
     VariableList variableList = new VariableList(builder.staticConstModifiers);
     variableList.type = enumType;
     int index = 0;
@@ -220,6 +221,7 @@ class EnumCreator {
 
       EnumFieldElementX field = new EnumFieldElementX(
           name, enumClass, variableList, definition, initializer);
+      enumValues.add(field);
       enumClass.addMember(field, compiler);
       index++;
     }
@@ -263,5 +265,7 @@ class EnumCreator {
         type: new FunctionType(toString, stringType));
     toString.functionSignatureCache = toStringSignature;
     enumClass.addMember(toString, compiler);
+
+    enumClass.enumValues = enumValues;
   }
 }