Handle fields with initializers in constant constructors.

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

Index: pkg/compiler/lib/src/resolution/constructors.dart
diff --git a/pkg/compiler/lib/src/resolution/constructors.dart b/pkg/compiler/lib/src/resolution/constructors.dart
index 7a4dbc68af735d296d314058213cbcc0a99162b1..a7845793ab7ac18fe8ed3f51ee49ab9301defa41 100644
--- a/pkg/compiler/lib/src/resolution/constructors.dart
+++ b/pkg/compiler/lib/src/resolution/constructors.dart
@@ -424,11 +424,24 @@ class InitializerResolver {
       constructorInvocation = resolveImplicitSuperConstructorSend();
     }
     if (isConst && isValidAsConstant) {
-      constructor.constantConstructor = new GenerativeConstantConstructor(
-          constructor.enclosingClass.thisType,
-          defaultValues,
-          fieldInitializers,
-          constructorInvocation);
+      constructor.enclosingClass.forEachInstanceField((_, FieldElement field) {
+        if (!fieldInitializers.containsKey(field)) {
+          visitor.resolution.ensureResolved(field);
+          // TODO(johnniwinther): Report error if `field.constant` is `null`.
+          if (field.constant != null) {
+            fieldInitializers[field] = field.constant;
+          } else {
+            isValidAsConstant = false;
+          }
+        }
+      });
+      if (isValidAsConstant) {
+        constructor.constantConstructor = new GenerativeConstantConstructor(
+            constructor.enclosingClass.thisType,
+            defaultValues,
+            fieldInitializers,
+            constructorInvocation);
+      }
     }
     return null; // If there was no redirection always return null.
   }