Expose CommentToken as analyzer public API

CommentToken is the static type of `Token.precedingComments`:
https://pub.dev/documentation/analyzer/5.13.0/dart_ast_token/Token/precedingComments.html
and so should be exposed as public API.

Cq-Include-Trybots: luci.dart.try:flutter-analyze-try,analyzer-win-release-try,pkg-win-release-try
Change-Id: I06e3e897bf310b9bc0e5067ab0f44db3a3e459c4
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/371946
Reviewed-by: Konstantin Shcheglov <[email protected]>
Reviewed-by: Brian Wilkerson <[email protected]>
Commit-Queue: Sam Rawlins <[email protected]>

Author: srawlins

pkg/analyzer/lib/dart/ast/token.dart

@@ -7,4 +7,4 @@
 library;
 
 export 'package:_fe_analyzer_shared/src/scanner/token.dart'
-    show Keyword, Token, TokenType, LanguageVersionToken;
+    show CommentToken, Keyword, Token, TokenType, LanguageVersionToken;

pkg/analyzer/lib/src/dart/analysis/unlinked_api_signature.dart

@@ -8,7 +8,6 @@ import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/src/dart/ast/invokes_super_self.dart';
 import 'package:analyzer/src/dart/ast/mixin_super_invoked_names.dart';
-import 'package:analyzer/src/dart/ast/token.dart';
 import 'package:analyzer/src/summary/api_signature.dart';
 
 /// Return the bytes of the unlinked API signature of the given [unit].

pkg/analyzer/lib/src/ignore_comments/ignore_info.dart

@@ -6,7 +6,6 @@ import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/error/error.dart';
 import 'package:analyzer/source/line_info.dart';
-import 'package:analyzer/src/dart/ast/token.dart';
 import 'package:analyzer/src/utilities/extensions/string.dart';
 
 /// The text and location of trailing unstructured comment text in an ignore

pkg/analyzer/lib/src/lint/util.dart

@@ -9,7 +9,6 @@ import 'package:analyzer/dart/analysis/utilities.dart';
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/dart/ast/visitor.dart';
-import 'package:analyzer/src/dart/ast/token.dart';
 import 'package:path/path.dart' as path;
 
 final _pubspec = RegExp(r'^[_]?pubspec\.yaml$');

pkg/analyzer_plugin/lib/src/utilities/completion/optype.dart

@@ -8,7 +8,6 @@ import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/type.dart';
 import 'package:analyzer/src/dart/ast/ast.dart';
 import 'package:analyzer/src/dart/ast/extensions.dart';
-import 'package:analyzer/src/dart/ast/token.dart';
 import 'package:analyzer/src/dart/element/element.dart';
 import 'package:analyzer_plugin/protocol/protocol_common.dart' hide Element;
 import 'package:analyzer_plugin/src/utilities/completion/completion_target.dart';