pkg/logging: expose static sorted const list of all levels

pkg/logging/lib/logging.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.
 
 /**
  * Support for logging.
  *
  * For information on installing and importing this library, see the
  * [logging package on pub.dartlang.org]
  * (http://pub.dartlang.org/packages/logging).
@@ skipping 293 matching lines @@
 
   /** Key for potential problems ([value] = 900). */
   static const Level WARNING = const Level('WARNING', 900);
 
   /** Key for serious failures ([value] = 1000). */
   static const Level SEVERE = const Level('SEVERE', 1000);
 
   /** Key for extra debugging loudness ([value] = 1200). */
   static const Level SHOUT = const Level('SHOUT', 1200);
 
+  static const List<Level> LEVELS = const
+      [ALL, FINEST, FINER, FINE, CONFIG, INFO, WARNING, SEVERE, SHOUT, OFF];
+
   bool operator ==(Object other) => other is Level && value == other.value;
   bool operator <(Level other) => value < other.value;
   bool operator <=(Level other) => value <= other.value;
   bool operator >(Level other) => value > other.value;
   bool operator >=(Level other) => value >= other.value;
   int compareTo(Level other) => value - other.value;
   int get hashCode => value;
   String toString() => name;
 }
 
@@ skipping 23 matching lines @@
   /** Associated stackTrace (if any) when recording errors messages. */
   final StackTrace stackTrace;
 
   LogRecord(this.level, this.message, this.loggerName, [this.error,
                                                         this.stackTrace])
       : time = new DateTime.now(),
         sequenceNumber = LogRecord._nextNumber++;
 
   String toString() => '[${level.name}] $loggerName: $message';
 }