Implement Dart 1.0 LUB algorithm (for interface types) in kernel.

pkg/kernel/lib/testing/mock_sdk_program.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 'package:kernel/ast.dart';
+
+/// Returns a [Program] object containing empty definitions of core SDK classes.
+Program createMockSdkProgram() {
+  var coreLib = new Library(Uri.parse('dart:core'));
+  var asyncLib = new Library(Uri.parse('dart:async'));
+  var internalLib = new Library(Uri.parse('dart:_internal'));
+
+  Class addClass(Library lib, Class c) {
+    lib.addClass(c);
+    return c;
+  }
+
+  var objectClass = addClass(coreLib, new Class(name: 'Object'));
+  var objectType = objectClass.rawType;
+
+  TypeParameter typeParam(String name, [DartType bound]) {
+    return new TypeParameter(name, bound ?? objectType);
+  }
+
+  Class class_(String name,
+      {Supertype supertype,
+      List<TypeParameter> typeParameters,
+      List<Supertype> implementedTypes}) {
+    return new Class(
+        name: name,
+        supertype: supertype ?? objectClass.asThisSupertype,
+        typeParameters: typeParameters,
+        implementedTypes: implementedTypes);
+  }
+
+  addClass(coreLib, class_('Null'));
+  addClass(coreLib, class_('bool'));
+  var num = addClass(coreLib, class_('num'));
+  addClass(coreLib, class_('String'));
+  var iterable =
+      addClass(coreLib, class_('Iterable', typeParameters: [typeParam('T')]));
+  {
+    var T = typeParam('T');
+    addClass(
+        coreLib,
+        class_('List', typeParameters: [
+          T
+        ], implementedTypes: [
+          new Supertype(iterable, [new TypeParameterType(T)])
+        ]));
+  }
+  addClass(
+      coreLib, class_('Map', typeParameters: [typeParam('K'), typeParam('V')]));
+  addClass(coreLib, class_('int', supertype: num.asThisSupertype));
+  addClass(coreLib, class_('double', supertype: num.asThisSupertype));
+  addClass(coreLib, class_('Iterator', typeParameters: [typeParam('T')]));
+  addClass(coreLib, class_('Symbol'));
+  addClass(coreLib, class_('Type'));
+  addClass(coreLib, class_('Function'));
+  addClass(coreLib, class_('Invocation'));
+  addClass(asyncLib, class_('Future', typeParameters: [typeParam('T')]));
+  addClass(asyncLib, class_('Stream', typeParameters: [typeParam('T')]));
+  addClass(internalLib, class_('Symbol'));
+
+  return new Program([coreLib, asyncLib, internalLib]);
+}