fix fasta summary builder

pkg/analyzer/lib/src/summary/fasta/summary_builder.dart

 // Copyright (c) 2017, 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.
 
 /// Logic to build unlinked summaries.
 library summary.src.summary_builder;
 
 import 'package:front_end/src/fasta/parser/class_member_parser.dart';
 import 'package:front_end/src/fasta/parser/identifier_context.dart';
 import 'package:front_end/src/fasta/parser/parser.dart';
@@ skipping 415 matching lines @@
 
   void handleIsOperator(Token operator, Token not, Token endToken) {
     debugEvent("Is");
     if (ignore) return;
     push(new Is(pop(), pop()));
   }
 
   void handleLiteralBool(Token token) {
     debugEvent("LiteralBool");
     if (ignore) return;
-    push(new BoolLiteral(token.value == 'true'));
+    push(new BoolLiteral(token.lexeme == 'true'));
   }
 
   void handleLiteralDouble(Token token) {
     debugEvent("LiteralDouble");
     if (ignore) return;
     push(new DoubleLiteral(double.parse(token.lexeme)));
   }
 
   void handleLiteralInt(Token token) {
     debugEvent("LiteralInt");
@@ skipping 137 matching lines @@
 
   // debug helpers
 
   void _endFunction();
 
   void _printExpression(Token token) {
     var current = token;
     var end = new ClassMemberParser(this).skipExpression(current);
     var str = new StringBuffer();
     while (current != end) {
-      if (!["(", ",", ")"].contains(current.value)) str.write(' ');
-      str.write(current.value);
+      if (!["(", ",", ")"].contains(current.lexeme)) str.write(' ');
+      str.write(current.lexeme);
       current = current.next;
     }
     print('exp: $str');
   }
 
   void _unhandledSend();
 }
 
 /// Builder for initializer expressions. These expressions exclude any nested
 /// expression that is not needed to infer strong mode types.
@@ skipping 853 matching lines @@
   }
 
   void handleNoTypeVariables(Token token) {
     debugEvent("NoTypeVariables");
     push(const []);
   }
 
   void handleOperatorName(Token operatorKeyword, Token token) {
     // TODO(sigmund): convert operator names to name used by summaries.
     debugEvent("OperatorName");
-    push(operatorKeyword.value);
+    push(operatorKeyword.lexeme);
   }
 
   void handleQualified(Token period) {
     debugEvent("handleQualified");
     String name = pop();
     String receiver = pop();
     push("$receiver.$name");
   }
 
   void handleStringPart(token) {
@@ skipping 110 matching lines @@
 }
 
 /// Internal representation of an initialized name.
 class _InitializedName {
   final String name;
   final UnlinkedExecutableBuilder initializer;
   _InitializedName(this.name, this.initializer);
 
   toString() => "II:" + (initializer != null ? "$name = $initializer" : name);
 }