Fix for issue 22052

pkg/analyzer/lib/src/generated/parser.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.parser;
 
 import "dart:math" as math;
@@ skipping 8594 matching lines @@
               [operator.lexeme]);
           return new PrefixExpression(
               operator,
               new SuperExpression(getAndAdvance()));
         }
       }
       return new PrefixExpression(operator, _parseAssignableExpression(false));
     } else if (_matches(TokenType.PLUS)) {
       _reportErrorForCurrentToken(ParserErrorCode.MISSING_IDENTIFIER);
       return _createSyntheticIdentifier();
-    } else if (_matchesString(_AWAIT)) {
+    } else if (_inAsync && _matchesString(_AWAIT)) {
       return _parseAwaitExpression();
     }
     return _parsePostfixExpression();
   }
 
   /**
    * Parse a string literal representing a URI.
    */
   StringLiteral _parseUri() {
     bool iskeywordAfterUri(Token token) =>
@@ skipping 3477 matching lines @@
    * Copy resolution data from one node to another.
    *
    * @param fromNode the node from which resolution information will be copied
    * @param toNode the node to which resolution information will be copied
    */
   static void copyResolutionData(AstNode fromNode, AstNode toNode) {
     ResolutionCopier copier = new ResolutionCopier();
     copier._isEqualNodes(fromNode, toNode);
   }
 }