Remove deprecated declarations from lib/src/lint/util.dart

This is not API, so if it is de-facto not used, we can just remove it.

Change-Id: Iac34884dd6982671eedf3005eab7790889e30148
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/224980
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>
Commit-Queue: Konstantin Shcheglov <scheglov@google.com>

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

@@ -12,19 +12,8 @@ import 'package:analyzer/dart/ast/visitor.dart';
 import 'package:analyzer/src/dart/ast/token.dart';
 import 'package:path/path.dart' as path;
 
-final _identifier = RegExp(r'^([(_|$)a-zA-Z]+([_a-zA-Z0-9])*)$');
-
-final _lowerCamelCase = RegExp(r'^(_)*[?$a-z][a-z0-9?$]*([A-Z][a-z0-9?$]*)*$');
-
-final _lowerCaseUnderScore = RegExp(r'^([a-z]+([_]?[a-z0-9]+)*)+$');
-
-final _lowerCaseUnderScoreWithDots =
-    RegExp(r'^[a-z][_a-z0-9]*(\.[a-z][_a-z0-9]*)*$');
-
 final _pubspec = RegExp(r'^[_]?pubspec\.yaml$');
 
-final _underscores = RegExp(r'^[_]+$');
-
 /// Create a library name prefix based on [libraryPath], [projectRoot] and
 /// current [packageName].
 String createLibraryNamePrefix(
@@ -50,37 +39,9 @@ String createLibraryNamePrefix(
 /// Returns `true` if this [fileName] is a Dart file.
 bool isDartFileName(String fileName) => fileName.endsWith('.dart');
 
-/// Returns `true` if this [name] is a legal Dart identifier.
-@deprecated // Never intended for public use.
-bool isIdentifier(String name) => _identifier.hasMatch(name);
-
-/// Returns `true` of the given [name] is composed only of `_`s.
-@deprecated // Never intended for public use.
-bool isJustUnderscores(String name) => _underscores.hasMatch(name);
-
-/// Returns `true` if this [id] is `lowerCamelCase`.
-@deprecated // Never intended for public use.
-bool isLowerCamelCase(String id) =>
-    id.length == 1 && isUpperCase(id.codeUnitAt(0)) ||
-    id == '_' ||
-    _lowerCamelCase.hasMatch(id);
-
-/// Returns `true` if this [id] is `lower_camel_case_with_underscores`.
-@deprecated // Never intended for public use.
-bool isLowerCaseUnderScore(String id) => _lowerCaseUnderScore.hasMatch(id);
-
-/// Returns `true` if this [id] is `lower_camel_case_with_underscores_or.dots`.
-@deprecated // Never intended for public use.
-bool isLowerCaseUnderScoreWithDots(String id) =>
-    _lowerCaseUnderScoreWithDots.hasMatch(id);
-
 /// Returns `true` if this [fileName] is a Pubspec file.
 bool isPubspecFileName(String fileName) => _pubspec.hasMatch(fileName);
 
-/// Returns `true` if the given code unit [c] is upper case.
-@deprecated // Never intended for public use.
-bool isUpperCase(int c) => c >= 0x40 && c <= 0x5A;
-
 class Spelunker {
   final String path;
   final IOSink sink;