update fasta scanner to generate two types of comments

pkg/front_end/lib/src/fasta/scanner/abstract_scanner.dart

 // Copyright (c) 2012, 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.abstract_scanner;
 
 import 'dart:collection' show ListMixin;
 
 import 'dart:typed_data' show Uint16List, Uint32List;
 
@@ skipping 168 matching lines @@
   /** Documentation in subclass [ArrayBasedScanner]. */
   int appendEndGroup(PrecedenceInfo info, int openKind);
 
   /** Documentation in subclass [ArrayBasedScanner]. */
   void appendGt(PrecedenceInfo info);
 
   /** Documentation in subclass [ArrayBasedScanner]. */
   void appendGtGt(PrecedenceInfo info);
 
   /** Documentation in subclass [ArrayBasedScanner]. */
-  void appendComment(start, bool asciiOnly);
+  void appendComment(start, PrecedenceInfo info, bool asciiOnly);
 
   /// Append [token] to the token stream.
   void appendErrorToken(ErrorToken token);
 
   /** Documentation in subclass [ArrayBasedScanner]. */
   void discardOpenLt();
 
   /// Return true when at EOF.
   bool atEndOfFile();
 
@@ skipping 72 matching lines @@
     }
 
     if (identical(next, $CLOSE_CURLY_BRACKET)) {
       return appendEndGroup(CLOSE_CURLY_BRACKET_INFO, OPEN_CURLY_BRACKET_TOKEN);
     }
 
     if (identical(next, $SLASH)) {
       return tokenizeSlashOrComment(next);
     }
 
-
     if (identical(next, $OPEN_CURLY_BRACKET)) {
       appendBeginGroup(OPEN_CURLY_BRACKET_INFO);
       return advance();
     }
 
     if (identical(next, $DQ) || identical(next, $SQ)) {
       return tokenizeString(next, scanOffset, false);
     }
 
-    if(identical(next, $_)){
+    if (identical(next, $_)) {
       return tokenizeKeywordOrIdentifier(next, true);
     }
 
     if (identical(next, $COLON)) {
       appendPrecedenceToken(COLON_INFO);
       return advance();
     }
 
     if (identical(next, $LT)) {
       return tokenizeLessThan(next);
@@ skipping 37 matching lines @@
     }
 
     if (identical(next, $BAR)) {
       return tokenizeBar(next);
     }
 
     if (identical(next, $PLUS)) {
       return tokenizePlus(next);
     }
 
-    if(identical(next, $$)){
+    if (identical(next, $$)) {
       return tokenizeKeywordOrIdentifier(next, true);
     }
 
     if (identical(next, $MINUS)) {
       return tokenizeMinus(next);
     }
 
     if (identical(next, $STAR)) {
       return tokenizeMultiply(next);
     }
@@ skipping 362 matching lines @@
 
   int tokenizeSingleLineComment(int next, int start) {
     bool asciiOnly = true;
     while (true) {
       next = advance();
       if (next > 127) asciiOnly = false;
       if (identical($LF, next) ||
           identical($CR, next) ||
           identical($EOF, next)) {
         if (!asciiOnly) handleUnicode(start);
-        appendComment(start, asciiOnly);
+        appendComment(start, SINGLE_LINE_COMMENT_INFO, asciiOnly);
         return next;
       }
     }
   }
 
   int tokenizeMultiLineComment(int next, int start) {
     bool asciiOnlyComment = true; // Track if the entire comment is ASCII.
     bool asciiOnlyLines = true; // Track ASCII since the last handleUnicode.
     int unicodeStart = start;
     int nesting = 1;
     next = advance();
     while (true) {
       if (identical($EOF, next)) {
         if (!asciiOnlyLines) handleUnicode(unicodeStart);
         unterminated('/*');
         break;
       } else if (identical($STAR, next)) {
         next = advance();
         if (identical($SLASH, next)) {
           --nesting;
           if (0 == nesting) {
             if (!asciiOnlyLines) handleUnicode(unicodeStart);
             next = advance();
-            appendComment(start, asciiOnlyComment);
+            appendComment(start, MULTI_LINE_COMMENT_INFO, asciiOnlyComment);
             break;
           } else {
             next = advance();
           }
         }
       } else if (identical($SLASH, next)) {
         next = advance();
         if (identical($STAR, next)) {
           next = advance();
           ++nesting;
@@ skipping 468 matching lines @@
       switchToUint32(newLength);
     }
   }
 
   void switchToUint32(int newLength) {
     final newArray = new Uint32List(newLength);
     newArray.setRange(0, arrayLength, array);
     array = newArray;
   }
 }