Revert "Add ClassMirror.isAbstract to the API and VM implementation."

tests/lib/mirrors/abstract_class_test.dart

-// 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 test.abstract_class_test;
-
-import 'dart:mirrors';
-import 'package:expect/expect.dart';
-
-abstract class Foo {
-  foo();
-}
-class Bar extends Foo {
-  foo() {}
-}
-
-abstract class FunctionFoo implements Function {
-  call();
-}
-class FunctionBar extends FunctionFoo {
-  call() {}
-}
-
-abstract class GenericFoo<T> {
-  T genericFoo();
-}
-class GenericBar<T> extends GenericFoo<T> {
-  T genericFoo() {}
-}
-
-void main() {
-  // FunctionTypeMirror
-  baz() {}
-  Expect.isFalse(reflect(baz).type.isAbstract);
-
-  return;  /// 01: ok
-
-  // Unbound ClassMirror
-  Expect.isTrue(reflectClass(Foo).isAbstract);
-  Expect.isFalse(reflectClass(Bar).isAbstract);
-  Expect.isTrue(reflect(new Bar()).type.superclass.isAbstract);
-  Expect.isFalse(reflect(new Bar()).type.isAbstract);
-
-  Expect.isTrue(reflectClass(FunctionFoo).isAbstract);
-  Expect.isFalse(reflectClass(FunctionBar).isAbstract);
-  Expect.isTrue(reflect(new FunctionBar()).type.superclass.isAbstract);
-  Expect.isFalse(reflect(new FunctionBar()).type.isAbstract);
-
-  Expect.isTrue(reflectClass(GenericFoo).isAbstract);
-  Expect.isFalse(reflectClass(GenericBar).isAbstract);
-
-  // Bound ClassMirror
-  Expect.isTrue(reflect(new GenericBar<int>()).type.superclass.isAbstract);
-  Expect.isFalse(reflect(new GenericBar<int>()).type.isAbstract);
-}