enable analyzer scanner adapter generic method support

pkg/analyzer/lib/src/fasta/token_utils.dart

 // Copyright (c) 2016, 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.analyzer.token_utils;
 
 import 'package:front_end/src/fasta/scanner/error_token.dart' show ErrorToken;
 
 import 'package:front_end/src/scanner/token.dart' show Keyword, Token;
 
@@ skipping 423 matching lines @@
     case TokenType.TILDE_SLASH:
       return symbol(TokenType.TILDE_SLASH);
     case TokenType.TILDE_SLASH_EQ:
       return symbol(TokenType.TILDE_SLASH_EQ);
     case TokenType.BACKPING:
       return symbol(TokenType.BACKPING);
     case TokenType.BACKSLASH:
       return symbol(TokenType.BACKSLASH);
     case TokenType.PERIOD_PERIOD_PERIOD:
       return symbol(TokenType.PERIOD_PERIOD_PERIOD);
-    // case TokenType.GENERIC_METHOD_TYPE_ASSIGN
-    // case TokenType.GENERIC_METHOD_TYPE_LIST
+    case TokenType.GENERIC_METHOD_TYPE_ASSIGN:
+      return new CommentToken.fromSubstring(
+          TokenType.GENERIC_METHOD_TYPE_ASSIGN,
+          token.lexeme,
+          0,
+          token.lexeme.length,
+          0);
+    case TokenType.GENERIC_METHOD_TYPE_LIST:
+      return new CommentToken.fromSubstring(TokenType.GENERIC_METHOD_TYPE_LIST,
+          token.lexeme, 0, token.lexeme.length, 0);
     default:
       return internalError('Unhandled token type ${token.type}');
   }
 }
 
 analyzer.Token toAnalyzerToken(Token token,
     [analyzer.CommentToken commentToken]) {
   if (token == null) return null;
   analyzer.Token makeStringToken(TokenType tokenType) {
     if (commentToken == null) {
@@ skipping 143 matching lines @@
   "hide": analyzer.Keyword.HIDE,
   "native": analyzer.Keyword.NATIVE,
   "of": analyzer.Keyword.OF,
   "on": analyzer.Keyword.ON,
   "patch": analyzer.Keyword.PATCH,
   "show": analyzer.Keyword.SHOW,
   "source": analyzer.Keyword.SOURCE,
   "sync": analyzer.Keyword.SYNC,
   "yield": analyzer.Keyword.YIELD,
 };