Parse assert statements with Fasta.

pkg/front_end/lib/src/fasta/kernel/body_builder.dart

 // Copyright (c) 2016, 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 fasta.body_builder;
 
 import '../parser/parser.dart' show FormalParameterType, optional;
 
 import '../parser/error_kind.dart' show ErrorKind;
 
@@ skipping 2004 matching lines @@
     exitLoopOrSwitch(result);
   }
 
   @override
   void handleEmptyStatement(Token token) {
     debugEvent("EmptyStatement");
     push(new EmptyStatement());
   }
 
   @override
-  void handleAssertStatement(
-      Token assertKeyword, Token commaToken, Token semicolonToken) {
+  void handleAssertStatement(Token assertKeyword, Token leftParenthesis,
+      Token commaToken, Token rightParenthesis, Token semicolonToken) {
     debugEvent("AssertStatement");
     Expression message = popForValueIfNotNull(commaToken);
     Expression condition = popForValue();
     push(new AssertStatement(condition, message));
   }
 
   @override
   void endYieldStatement(Token yieldToken, Token starToken, Token endToken) {
     debugEvent("YieldStatement");
     push(new YieldStatement(popForValue(), isYieldStar: starToken != null));
@@ skipping 732 matching lines @@
   } else if (node is PrefixBuilder) {
     return node.name;
   } else if (node is ThisAccessor) {
     return node.isSuper ? "super" : "this";
   } else if (node is BuilderAccessor) {
     return node.plainNameForRead;
   } else {
     return internalError("Unhandled: ${node.runtimeType}");
   }
 }