Add implicit super() call

frog/member.dart

Index: frog/member.dart
diff --git a/frog/member.dart b/frog/member.dart
index 4f73bcf5cb8c08de011cf0e03038c6bd141ad2f1..2e74a9adb919d466f20013a9658ca9eb710facec 100644
--- a/frog/member.dart
+++ b/frog/member.dart
@@ -135,10 +135,10 @@ class Member implements Named {
   void provideFieldSyntax() {}
   void providePropertySyntax() {}
 
-  Definition get initDelegate() {
+  Member get initDelegate() {
     world.internalError('cannot have initializers', span);
   }
-  Definition set initDelegate(ctor) {
+  Member set initDelegate(ctor) {
     world.internalError('cannot have initializers', span);
   }
 
@@ -576,8 +576,8 @@ class ConcreteMember extends Member {
   Definition get definition() => baseMember.definition;
 
   // TODO(sigmund): this is EGREGIOUS
-  Definition get initDelegate() => baseMember.initDelegate;
-  Definition set initDelegate(ctor) { baseMember.initDelegate = ctor; }
+  Member get initDelegate() => baseMember.initDelegate;
+  Member set initDelegate(ctor) { baseMember.initDelegate = ctor; }
 
   Type resolveType(TypeReference node, bool isRequired) {
     var type = baseMember.resolveType(node, isRequired);