Allow error-recovery in top-level nodes.

dart/frog/leg/scanner/parser.dart

 // Copyright (c) 2011, 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.
 
 /**
  * An event generating parser of Dart programs. This parser expects
  * all tokens in a linked list.
  */
 class Parser<L extends Listener> {
   final L listener;
@@ skipping 287 matching lines @@
         case kind === EQ_TOKEN:
           break LOOP;
         default:
           previous = token;
           token = next(token);
           break;
       }
     }
     token = parseIdentifier(previous);
     bool isField;
-    if (optional('(', token)) {
-      isField = false;
-    } else if (optional('=', token) || optional(';', token)) {
-      isField = true;
-    } else {
-      token = listener.unexpected(token);
+    while (true) {
+      // Loop to allow the listener to rewrite the token stream to
+      // make the parser happy.
+      if (optional('(', token)) {
+        isField = false;
+        break;
+      } else if (optional('=', token) || optional(';', token)) {
+        isField = true;
+        break;
+      } else {
+        token = listener.unexpected(token);
+      }
     }
     while (token !== null &&
            token.kind !== LBRACE_TOKEN &&
            token.kind !== SEMICOLON_TOKEN) {
       token = next(token);
     }
     if (!optional(';', token)) {
       token = skipBlock(token);
     }
     if (isField) {
@@ skipping 375 matching lines @@
     if (optional(';', token)) {
       listener.endRethrowStatement(throwToken, token);
       return token.next;
     } else {
       token = parseExpression(token);
       listener.endThrowStatement(throwToken, token);
       return expectSemicolon(token);
     }
   }
 }