Fix some bad documentation links.

sdk/lib/developer/timeline.dart

 // Copyright (c) 2015, 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.
 
 part of dart.developer;
 
 const bool _isProduct = const bool.fromEnvironment("dart.vm.product");
 
 typedef dynamic TimelineSyncFunction();
 typedef Future TimelineAsyncFunction();
@@ skipping 79 matching lines @@
   static final int _isolateId = _getIsolateNum();
   static final String _isolateIdString = _isolateId.toString();
 }
 
 /// An asynchronous task on the timeline. An asynchronous task can have many
 /// (nested) synchronous operations. Synchronous operations can live longer than
 /// the current isolate event. To pass a [TimelineTask] to another isolate,
 /// you must first call [pass] to get the task id and then construct a new
 /// [TimelineTask] in the other isolate.
 class TimelineTask {
-  /// Create a task. [taskId] will be set by the system.
+  /// Create a task. The task ID will be set by the system.
   TimelineTask() : _taskId = _getNextAsyncId() {}
 
   /// Create a task with an explicit [taskId]. This is useful if you are
   /// passing a task from one isolate to another.
   TimelineTask.withTaskId(int taskId) : _taskId = taskId {
     if (taskId is! int) {
       throw new ArgumentError.value(taskId, 'taskId', 'Must be an int');
     }
   }
 
@@ skipping 168 matching lines @@
 external void _reportTaskEvent(int start, int taskId, String phase,
     String category, String name, String argumentsAsJson);
 
 /// Reports a complete synchronous event.
 external void _reportCompleteEvent(int start, int startCpu, String category,
     String name, String argumentsAsJson);
 
 /// Reports an instant event.
 external void _reportInstantEvent(
     int start, String category, String name, String argumentsAsJson);