Revert "Tweak public APIs and use them in patch_sdk, dart2js, and kernel-service."

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

Index: pkg/front_end/lib/src/fasta/kernel/utils.dart
diff --git a/pkg/front_end/lib/src/fasta/kernel/utils.dart b/pkg/front_end/lib/src/fasta/kernel/utils.dart
index f77b16dd9d11fd3388a66c7f431f6c0c2d40ca24..df9748ba387553c27d01cb8690ec00f48eefa775 100644
--- a/pkg/front_end/lib/src/fasta/kernel/utils.dart
+++ b/pkg/front_end/lib/src/fasta/kernel/utils.dart
@@ -8,7 +8,6 @@ import 'dart:io';
 import 'package:front_end/src/scanner/token.dart' show Token;
 import 'package:kernel/ast.dart';
 import 'package:kernel/binary/ast_to_binary.dart';
-import 'package:kernel/binary/limited_ast_to_binary.dart';
 import 'package:kernel/text/ast_to_text.dart';
 
 /// A null-aware alternative to `token.offset`.  If [token] is `null`, returns
@@ -40,26 +39,3 @@ Future<Null> writeProgramToFile(Program program, Uri uri) async {
     await sink.close();
   }
 }
-
-/// Serialize the libraries in [program] that match [filter].
-List<int> serializeProgram(Program program,
-    {bool filter(Library library), bool excludeUriToSource: false}) {
-  ByteSink byteSink = new ByteSink();
-  BinaryPrinter printer = filter == null && !excludeUriToSource
-      ? new BinaryPrinter(byteSink)
-      : new LimitedBinaryPrinter(
-          byteSink, filter ?? (_) => true, excludeUriToSource);
-  printer.writeProgramFile(program);
-  return byteSink.builder.takeBytes();
-}
-
-/// A [Sink] that directly writes data into a byte builder.
-class ByteSink implements Sink<List<int>> {
-  final BytesBuilder builder = new BytesBuilder();
-
-  void add(List<int> data) {
-    builder.add(data);
-  }
-
-  void close() {}
-}