Scanner/parser support for DEP 9 (null-aware operators).

pkg/analyzer/test/generated/ast_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.
 
 // This code was auto-generated, is not intended to be edited, and is subject to
 // significant change. Please see the README file for more information.
 
 library engine.ast_test;
 
 import 'package:analyzer/src/generated/ast.dart';
@@ skipping 2830 matching lines @@
   void test_visitPrefixExpression() {
     _assertSource("-a", AstFactory.prefixExpression(
         TokenType.MINUS, AstFactory.identifier3("a")));
   }
 
   void test_visitPropertyAccess() {
     _assertSource(
         "a.b", AstFactory.propertyAccess2(AstFactory.identifier3("a"), "b"));
   }
 
+  void test_visitPropertyAccess_conditional() {
+    _assertSource("a?.b", AstFactory.propertyAccess2(
+        AstFactory.identifier3("a"), "b", TokenType.QUESTION_PERIOD));
+  }
+
   void test_visitRedirectingConstructorInvocation_named() {
     _assertSource(
         "this.c()", AstFactory.redirectingConstructorInvocation2("c"));
   }
 
   void test_visitRedirectingConstructorInvocation_unnamed() {
     _assertSource("this()", AstFactory.redirectingConstructorInvocation());
   }
 
   void test_visitRethrowExpression() {
@@ skipping 361 matching lines @@
   static const List<WrapperKind> values = const [
     PREFIXED_LEFT,
     PREFIXED_RIGHT,
     PROPERTY_LEFT,
     PROPERTY_RIGHT,
     NONE
   ];
 
   const WrapperKind(String name, int ordinal) : super(name, ordinal);
 }