Revert "Revert "Use native async/await support in pub.""

sdk/lib/_internal/pub_generated/asset/dart/serialize/transformer.dart

Index: sdk/lib/_internal/pub_generated/asset/dart/serialize/transformer.dart
diff --git a/sdk/lib/_internal/pub_generated/asset/dart/serialize/transformer.dart b/sdk/lib/_internal/pub_generated/asset/dart/serialize/transformer.dart
deleted file mode 100644
index 16d02deb5790116cc24428521f357ba1fbd6f872..0000000000000000000000000000000000000000
--- a/sdk/lib/_internal/pub_generated/asset/dart/serialize/transformer.dart
+++ /dev/null
@@ -1,126 +0,0 @@
-// Copyright (c) 2014, 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.
-
-library pub.asset.serialize.transformer;
-
-import 'dart:async';
-import 'dart:isolate';
-
-import 'package:barback/barback.dart';
-
-import '../serialize.dart';
-import 'transform.dart';
-
-/// Converts [transformer] into a serializable map.
-Map _serializeTransformer(Transformer transformer) {
-  var port = new ReceivePort();
-  port.listen((wrappedMessage) {
-    respond(wrappedMessage, (message) {
-      if (message['type'] == 'isPrimary') {
-        return transformer.isPrimary(deserializeId(message['id']));
-      } else if (message['type'] == 'declareOutputs') {
-        return new Future.sync(() {
-          return (transformer as DeclaringTransformer).declareOutputs(
-              new ForeignDeclaringTransform(message['transform']));
-        }).then((_) => null);
-      } else {
-        assert(message['type'] == 'apply');
-
-        // Make sure we return null so that if the transformer's [apply] returns
-        // a non-serializable value it doesn't cause problems.
-        return new Future.sync(() {
-          return transformer.apply(new ForeignTransform(message['transform']));
-        }).then((_) => null);
-      }
-    });
-  });
-
-  var type;
-  if (transformer is LazyTransformer) {
-    type = 'LazyTransformer';
-  } else if (transformer is DeclaringTransformer) {
-    type = 'DeclaringTransformer';
-  } else {
-    type = 'Transformer';
-  }
-
-  return {
-    'type': type,
-    'toString': transformer.toString(),
-    'port': port.sendPort
-  };
-}
-
-/// Converts [transformer] into a serializable map.
-Map _serializeAggregateTransformer(AggregateTransformer transformer) {
-  var port = new ReceivePort();
-  port.listen((wrappedMessage) {
-    respond(wrappedMessage, (message) {
-      if (message['type'] == 'classifyPrimary') {
-        return transformer.classifyPrimary(deserializeId(message['id']));
-      } else if (message['type'] == 'declareOutputs') {
-        return new Future.sync(() {
-          return (transformer as DeclaringAggregateTransformer).declareOutputs(
-              new ForeignDeclaringAggregateTransform(message['transform']));
-        }).then((_) => null);
-      } else {
-        assert(message['type'] == 'apply');
-
-        // Make sure we return null so that if the transformer's [apply] returns
-        // a non-serializable value it doesn't cause problems.
-        return new Future.sync(() {
-          return transformer.apply(
-              new ForeignAggregateTransform(message['transform']));
-        }).then((_) => null);
-      }
-    });
-  });
-
-  var type;
-  if (transformer is LazyAggregateTransformer) {
-    type = 'LazyAggregateTransformer';
-  } else if (transformer is DeclaringAggregateTransformer) {
-    type = 'DeclaringAggregateTransformer';
-  } else {
-    type = 'AggregateTransformer';
-  }
-
-  return {
-    'type': type,
-    'toString': transformer.toString(),
-    'port': port.sendPort
-  };
-}
-
-// Converts [group] into a serializable map.
-Map _serializeTransformerGroup(TransformerGroup group) {
-  if (group.phases == null) {
-    throw "TransformerGroup $group phases cannot be null.";
-  }
-
-  return {
-    'type': 'TransformerGroup',
-    'toString': group.toString(),
-    'phases': group.phases.map((phase) {
-      return phase.map(serializeTransformerLike).toList();
-    }).toList()
-  };
-}
-
-/// Converts [transformerLike] into a serializable map.
-///
-/// [transformerLike] can be a [Transformer], an [AggregateTransformer], or a
-/// [TransformerGroup].
-Map serializeTransformerLike(transformerLike) {
-  if (transformerLike is Transformer) {
-    return _serializeTransformer(transformerLike);
-  } else if (transformerLike is TransformerGroup) {
-    return _serializeTransformerGroup(transformerLike);
-  } else {
-    // This has to be last, since "transformerLike is AggregateTransformer" will
-    // throw on older versions of barback.
-    assert(transformerLike is AggregateTransformer);
-    return _serializeAggregateTransformer(transformerLike);
-  }
-}