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

pkg/front_end/lib/src/incremental_kernel_generator_impl.dart

 // Copyright (c) 2017, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 import 'dart:async';
-import 'dart:io';
 
 import 'package:front_end/file_system.dart';
 import 'package:front_end/incremental_kernel_generator.dart';
 import 'package:front_end/src/base/api_signature.dart';
 import 'package:front_end/src/base/performace_logger.dart';
 import 'package:front_end/src/base/processed_options.dart';
 import 'package:front_end/src/fasta/dill/dill_library_builder.dart';
 import 'package:front_end/src/fasta/dill/dill_target.dart';
 import 'package:front_end/src/fasta/kernel/kernel_target.dart';
+import 'package:front_end/src/fasta/kernel/utils.dart';
 import 'package:front_end/src/fasta/ticker.dart';
 import 'package:front_end/src/fasta/translate_uri.dart';
 import 'package:front_end/src/incremental/byte_store.dart';
 import 'package:front_end/src/incremental/file_state.dart';
 import 'package:kernel/binary/ast_from_binary.dart';
-import 'package:kernel/binary/limited_ast_to_binary.dart';
 import 'package:kernel/kernel.dart' hide Source;
 import 'package:kernel/target/targets.dart' show TargetFlags;
 import 'package:kernel/target/vm_fasta.dart' show VmFastaTarget;
 import 'package:meta/meta.dart';
 
-class ByteSink implements Sink<List<int>> {
-  final BytesBuilder builder = new BytesBuilder();
-
-  void add(List<int> data) {
-    builder.add(data);
-  }
-
-  void close() {}
-}
-
 /// Implementation of [IncrementalKernelGenerator].
 ///
 /// TODO(scheglov) Update the documentation.
 ///
 /// Theory of operation: an instance of [IncrementalResolvedAstGenerator] is
 /// used to obtain resolved ASTs, and these are fed into kernel code generation
 /// logic.
 class IncrementalKernelGeneratorImpl implements IncrementalKernelGenerator {
   /// The version of data format, should be incremented on every format change.
   static const int DATA_VERSION = 1;
@@ skipping 214 matching lines @@
 
       // Add newly compiled libraries into DILL.
       await appendNewDillLibraries(program);
 
       List<Library> kernelLibraries = program.libraries
           .where((library) => libraryUris.contains(library.importUri))
           .toList();
 
       _logger.run('Serialize ${kernelLibraries.length} libraries', () {
         program.uriToSource.clear();
-        List<int> bytes = _writeProgramBytes(program, kernelLibraries.contains);
+        List<int> bytes =
+            serializeProgram(program, filter: kernelLibraries.contains);
         _byteStore.put(kernelKey, bytes);
         _logger.writeln('Stored ${bytes.length} bytes.');
       });
 
       return new _LibraryCycleResult(cycle, signature, kernelLibraries);
     });
   }
 
   /// Compute exports scopes for a new strongly connected cycle of [libraries].
   /// The [dillTarget] can be used to access libraries from previous cycles.
@@ skipping 85 matching lines @@
 
       // The file graph might have changed, perform GC.
       var removedFiles = _fsState.gc(_entryPoint);
       if (removedFiles.isNotEmpty && _watchFn != null) {
         for (var removedFile in removedFiles) {
           await _watchFn(removedFile.fileUri, false);
         }
       }
     });
   }
-
-  List<int> _writeProgramBytes(Program program, bool filter(Library library)) {
-    ByteSink byteSink = new ByteSink();
-    new LimitedBinaryPrinter(byteSink, filter).writeProgramFile(program);
-    return byteSink.builder.takeBytes();
-  }
 }
 
 /// Compilation result for a library cycle.
 class _LibraryCycleResult {
   final LibraryCycle cycle;
 
   /// The signature of the result.
   ///
   /// It is based on the full content of the libraries in the [cycle], and
   /// either API signatures of the transitive dependencies (usually), or
   /// the full content of them (in the [cycle] has a library with a mixin
   /// application).
   final String signature;
 
   /// Kernel libraries for libraries in the [cycle].  Bodies of dependencies
   /// are not included, but but references to those dependencies are included.
   final List<Library> kernelLibraries;
 
   _LibraryCycleResult(this.cycle, this.signature, this.kernelLibraries);
 }
 
 @visibleForTesting
 class _TestView {
   /// The list of [LibraryCycle]s compiled for the last delta.
   /// It does not include libraries which were read from the cache.
   final List<LibraryCycle> compiledCycles = [];
 }