Store the async-await compiled pub code directly in the repo.

sdk/lib/_internal/pub_generated/lib/src/source.dart

Index: sdk/lib/_internal/pub_generated/lib/src/source.dart
diff --git a/sdk/lib/_internal/pub_generated/lib/src/source.dart b/sdk/lib/_internal/pub_generated/lib/src/source.dart
new file mode 100644
index 0000000000000000000000000000000000000000..f5a33fedf496d899e3bdb8349b15255f3c1d1f04
--- /dev/null
+++ b/sdk/lib/_internal/pub_generated/lib/src/source.dart
@@ -0,0 +1,45 @@
+library pub.source;
+import 'dart:async';
+import 'package.dart';
+import 'pubspec.dart';
+import 'system_cache.dart';
+import 'version.dart';
+abstract class Source {
+  String get name;
+  final bool hasMultipleVersions = false;
+  bool get isDefault => systemCache.sources.defaultSource == this;
+  SystemCache get systemCache {
+    assert(_systemCache != null);
+    return _systemCache;
+  }
+  SystemCache _systemCache;
+  void bind(SystemCache systemCache) {
+    assert(_systemCache == null);
+    this._systemCache = systemCache;
+  }
+  Future<List<Version>> getVersions(String name, description) {
+    var id = new PackageId(name, this.name, Version.none, description);
+    return describe(id).then((pubspec) => [pubspec.version]);
+  }
+  Future<Pubspec> describe(PackageId id) {
+    if (id.isRoot) throw new ArgumentError("Cannot describe the root package.");
+    if (id.source != name) {
+      throw new ArgumentError("Package $id does not use source $name.");
+    }
+    return doDescribe(id);
+  }
+  Future<Pubspec> doDescribe(PackageId id);
+  Future get(PackageId id, String symlink);
+  Future<String> getDirectory(PackageId id);
+  dynamic parseDescription(String containingPath, description,
+      {bool fromLockFile: false});
+  dynamic serializeDescription(String containingPath, description) {
+    return description;
+  }
+  String formatDescription(String containingPath, description) {
+    return description.toString();
+  }
+  bool descriptionsEqual(description1, description2);
+  Future<PackageId> resolveId(PackageId id) => new Future.value(id);
+  String toString() => name;
+}