Add support for the new function-type syntax.

pkg/front_end/lib/src/fasta/scanner/token.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.
 
 library fasta.scanner.token;
 
 import 'dart:collection' show
     HashSet;
 
 import 'dart:convert' show
@@ skipping 100 matching lines @@
     }
   }
 
   /// The character offset of the end of this token within the source text.
   int get charEnd => charOffset + charCount;
 
   bool get isEof => false;
 }
 
 /**
- * A [SymbolToken] represents the symbol in its precendence info.
+ * A [SymbolToken] represents the symbol in its precedence info.
  * Also used for end of file with EOF_INFO.
  */
 class SymbolToken extends Token {
   final PrecedenceInfo info;
 
   SymbolToken(this.info, int charOffset) : super(charOffset);
 
   String get value => info.value;
 
   String get stringValue => info.value;
@@ skipping 235 matching lines @@
       value == '<=' ||
       value == '<' ||
       value == '&' ||
       value == '^' ||
       value == '|';
 }
 
 bool isTernaryOperator(String value) => value == '[]=';
 
 bool isMinusOperator(String value) => value == '-';