Resynthesize constructor initializers from Kernel.

pkg/front_end/lib/src/fasta/kernel/fasta_accessors.dart

Index: pkg/front_end/lib/src/fasta/kernel/fasta_accessors.dart
diff --git a/pkg/front_end/lib/src/fasta/kernel/fasta_accessors.dart b/pkg/front_end/lib/src/fasta/kernel/fasta_accessors.dart
index 3b9ecc699647968b926aec9303c9a38fbaf93718..8583989de9deee06daff70a9d6b8e9096e3b2fe2 100644
--- a/pkg/front_end/lib/src/fasta/kernel/fasta_accessors.dart
+++ b/pkg/front_end/lib/src/fasta/kernel/fasta_accessors.dart
@@ -88,10 +88,10 @@ abstract class BuilderHelper {
   Initializer buildInvalidInitializer(Expression expression, [int offset]);
 
   Initializer buildFieldInitializer(
-      String name, int offset, Expression expression);
+      bool isSynthetic, String name, int offset, Expression expression);
 
   Initializer buildSuperInitializer(
-      Constructor constructor, Arguments arguments,
+      bool isSynthetic, Constructor constructor, Arguments arguments,
       [int offset]);
 
   Initializer buildRedirectingInitializer(
@@ -396,7 +396,8 @@ class ThisAccessor extends FastaAccessor {
               isSuper: isSuper, name: name.name, offset: offset),
           offset);
     } else if (isSuper) {
-      return helper.buildSuperInitializer(constructor, arguments, offset);
+      return helper.buildSuperInitializer(
+          false, constructor, arguments, offset);
     } else {
       return helper.buildRedirectingInitializer(constructor, arguments, offset);
     }