Revert "Create an app snapshot of the Dart front end."

utils/kernel-service/kernel-service.dart

-// Copyright (c) 2016, 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.
-
-// This is an interface to the Dart Kernel parser and Kernel binary generator.
-// It is used by the kernel-isolate to load Dart source code and generate
-// Kernel binary format.
-
-import 'dart:isolate';
-import 'dart:async';
-import 'dart:io';
-import 'dart:typed_data';
-
-import 'package:kernel/binary/ast_to_binary.dart';
-import 'package:kernel/analyzer/loader.dart';
-import 'package:kernel/kernel.dart';
-import 'package:kernel/target/targets.dart';
-
-const verbose = false;
-
-class DataSink implements Sink<List<int>> {
-  final BytesBuilder builder = new BytesBuilder();
-
-  void add(List<int> data) {
-    builder.add(data);
-  }
-
-  void close() {
-    // Nothing to do.
-  }
-}
-
-Future<Uint8List> parseScript(
-    Uri fileName, String packageConfig, String sdkPath) async {
-  if (!FileSystemEntity.isFileSync(fileName.path)) {
-    throw "Input file '${fileName.path}' does not exist.";
-  }
-
-  if (!FileSystemEntity.isDirectorySync(sdkPath)) {
-    throw "Patched sdk directory not found at $sdkPath";
-  }
-
-  Target target = getTarget("vm", new TargetFlags(strongMode: false));
-  DartOptions dartOptions = new DartOptions(
-      strongMode: false,
-      strongModeSdk: false,
-      sdk: sdkPath,
-      packagePath: packageConfig,
-      customUriMappings: const {},
-      declaredVariables: const {});
-  DartLoader loader =
-      await new DartLoaderBatch().getLoader(new Repository(), dartOptions);
-  var program = loader.loadProgram(fileName, target: target);
-
-  var errors = loader.errors;
-  if (errors.isNotEmpty) {
-    throw loader.errors.first;
-  }
-
-  // Link program into one file, cf. --link option in dartk.
-  target.transformProgram(program);
-
-  // Write the program to a list of bytes and return it.
-  var sink = new DataSink();
-  new BinaryPrinter(sink).writeProgramFile(program);
-  return sink.builder.takeBytes();
-}
-
-Future _processLoadRequest(request) async {
-  if (verbose) {
-    print("FROM DART KERNEL: load request: $request");
-    print("FROM DART KERNEL: package: ${Platform.packageConfig}");
-    print("FROM DART KERNEL: exec: ${Platform.resolvedExecutable}");
-  }
-
-  int tag = request[0];
-  SendPort port = request[1];
-  String inputFileUrl = request[2];
-  Uri scriptUri = Uri.parse(inputFileUrl);
-  Uri packagesUri = Uri.parse(Platform.packageConfig ?? ".packages");
-  Uri patchedSdk =
-      Uri.parse(Platform.resolvedExecutable).resolve("patched_sdk");
-
-  var result;
-  try {
-    result = await parseScript(scriptUri, packagesUri.path, patchedSdk.path);
-  } catch (error) {
-    tag = -tag; // Mark reply as an exception.
-    result = error.toString();
-  }
-
-  port.send([tag, inputFileUrl, inputFileUrl, null, result]);
-}
-
-// This entry point is used when running in the kernel isolate.
-start() => new RawReceivePort()..handler = _processLoadRequest;
-
-// This entry point is used when creating an app snapshot. The argument provides
-// a script to compile to warm-up generated code.
-main(args) {
-  var tag = 1;
-  var scriptUri = args[0];
-  var responsePort = new RawReceivePort();
-  responsePort.handler = (response) {
-    if (response[0] == tag) {
-      // Success.
-      responsePort.close();
-    } else if (response[0] == -tag) {
-      // Compilation error.
-      throw response[4];
-    } else {
-      throw "Unexpected response: $response";
-    }
-  };
-  var request = [tag, responsePort.sendPort, scriptUri];
-  _processLoadRequest(request);
-}