rename fasta.Token.value --> lexeme

pkg/front_end/lib/src/fasta/source/stack_listener.dart

Index: pkg/front_end/lib/src/fasta/source/stack_listener.dart
diff --git a/pkg/front_end/lib/src/fasta/source/stack_listener.dart b/pkg/front_end/lib/src/fasta/source/stack_listener.dart
index 28411993fe6cfb6e5e92f19ce09b3dd504c3db67..b801ca118b74f1f9cf616c1b2ed70e41b2c17ba2 100644
--- a/pkg/front_end/lib/src/fasta/source/stack_listener.dart
+++ b/pkg/front_end/lib/src/fasta/source/stack_listener.dart
@@ -111,7 +111,7 @@ abstract class StackListener extends Listener {
   @override
   void handleIdentifier(Token token, IdentifierContext context) {
     debugEvent("handleIdentifier");
-    push(token.value);
+    push(token.lexeme);
   }
 
   @override
@@ -214,7 +214,7 @@ abstract class StackListener extends Listener {
     debugEvent("endLiteralString");
     if (interpolationCount == 0) {
       Token token = pop();
-      push(unescapeString(token.value));
+      push(unescapeString(token.lexeme));
     } else {
       internalError("String interpolation not implemented.");
     }