Fix missing parenthesis.

pkg/compiler/lib/src/parser/parser.dart

 // Copyright (c) 2012, 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 dart2js.parser;
 
 import '../common.dart';
 import '../tokens/keyword.dart' show Keyword;
 import '../tokens/precedence.dart' show PrecedenceInfo;
 import '../tokens/precedence_constants.dart'
@@ skipping 414 matching lines @@
 
   Token parseFormalParameter(Token token, FormalParameterType type) {
     token = parseMetadataStar(token, forParameter: true);
     listener.beginFormalParameter(token);
 
     // Skip over `covariant` token, if the next token is an identifier or
     // modifier.
     // This enables the case where `covariant` is the name of the parameter:
     //    void foo(covariant);
     if (identical(token.stringValue, 'covariant') &&
-        token.next.isIdentifier() || isModifier(token.next)) {
+        (token.next.isIdentifier() || isModifier(token.next))) {
       token = token.next;
     }
     token = parseModifiers(token);
     // TODO(ahe): Validate that there are formal parameters if void.
     token = parseReturnTypeOpt(token);
     Token thisKeyword = null;
     if (optional('this', token)) {
       thisKeyword = token;
       // TODO(ahe): Validate field initializers are only used in
       // constructors, and not for function-typed arguments.
@@ skipping 2552 matching lines @@
     }
     listener.handleContinueStatement(hasTarget, continueKeyword, token);
     return expectSemicolon(token);
   }
 
   Token parseEmptyStatement(Token token) {
     listener.handleEmptyStatement(token);
     return expectSemicolon(token);
   }
 }