update the analyzer and analysis server perf tags

pkg/analysis_server/lib/src/analysis_server.dart

 // Copyright (c) 2014, 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.
 
 import 'dart:async';
 import 'dart:collection';
 import 'dart:core';
 import 'dart:io' as io;
 import 'dart:math' show max;
 
@@ skipping 1074 matching lines @@
       contextAnalysisDoneCompleters[context] = completer;
     }
     return completer.future;
   }
 
   /**
    * Perform the next available [ServerOperation].
    */
   void performOperation() {
     assert(performOperationPending);
-    PerformanceTag.UNKNOWN.makeCurrent();
+    PerformanceTag.unknown.makeCurrent();
     performOperationPending = false;
     if (!running) {
       // An error has occurred, or the connection to the client has been
       // closed, since this method was scheduled on the event queue.  So
       // don't do anything.  Instead clear the operation queue.
       operationQueue.clear();
       return;
     }
     // prepare next operation
     ServerOperation operation = operationQueue.take();
@@ skipping 1230 matching lines @@
       }
     }
   }
 }
 
 /**
  * Container with global [AnalysisServer] performance statistics.
  */
 class ServerPerformanceStatistics {
   /**
+   * The [PerformanceTag] for `package:analysis_server`.
+   */
+  static PerformanceTag server = new PerformanceTag('server');
+
+  /**
    * The [PerformanceTag] for time spent in [ExecutionDomainHandler].
    */
   static PerformanceTag executionNotifications =
       new PerformanceTag('executionNotifications');
 
   /**
    * The [PerformanceTag] for time spent performing a _DartIndexOperation.
    */
   static PerformanceTag indexOperation = new PerformanceTag('indexOperation');
 
   /**
    * The [PerformanceTag] for time spent between calls to
    * AnalysisServer.performOperation when the server is not idle.
    */
   static PerformanceTag intertask = new PerformanceTag('intertask');
 
   /**
    * The [PerformanceTag] for time spent between calls to
    * AnalysisServer.performOperation when the server is idle.
    */
   static PerformanceTag idle = new PerformanceTag('idle');
 
   /**
    * The [PerformanceTag] for time spent in
    * PerformAnalysisOperation._sendNotices.
    */
-  static PerformanceTag notices = new PerformanceTag('notices');
+  static PerformanceTag notices = server.createChild('notices');
 
   /**
    * The [PerformanceTag] for time spent running pub.
    */
-  static PerformanceTag pub = new PerformanceTag('pub');
+  static PerformanceTag pub = server.createChild('pub');
 
   /**
    * The [PerformanceTag] for time spent in server communication channels.
    */
-  static PerformanceTag serverChannel = new PerformanceTag('serverChannel');
+  static PerformanceTag serverChannel = server.createChild('channel');
 
   /**
    * The [PerformanceTag] for time spent in server request handlers.
    */
-  static PerformanceTag serverRequests = new PerformanceTag('serverRequests');
+  static PerformanceTag serverRequests = server.createChild('requests');
 
   /**
    * The [PerformanceTag] for time spent in split store microtasks.
    */
   static PerformanceTag splitStore = new PerformanceTag('splitStore');
 }
 
 /**
  * Used to record server exceptions.
  */
 class ServerException {
   final String message;
   final dynamic exception;
   final StackTrace stackTrace;
   final bool fatal;
 
   ServerException(this.message, this.exception, this.stackTrace, this.fatal);
 
   @override
   String toString() => message;
 }