Next steps toward HTML support

pkg/analyzer/lib/src/task/driver.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.
 
 library analyzer.src.task.driver;
 
 import 'dart:async';
 import 'dart:collection';
 
 import 'package:analyzer/src/context/cache.dart';
@@ skipping 139 matching lines @@
    */
   WorkOrder createWorkOrderForResult(
       AnalysisTarget target, ResultDescriptor result) {
     CacheEntry entry = context.getCacheEntry(target);
     CacheState state = entry.getState(result);
     if (state == CacheState.VALID ||
         state == CacheState.ERROR ||
         state == CacheState.IN_PROCESS) {
       return null;
     }
+    TaskDescriptor taskDescriptor = taskManager.findTask(target, result);
     try {
-      TaskDescriptor taskDescriptor = taskManager.findTask(target, result);
       WorkItem workItem = new WorkItem(context, target, taskDescriptor, result);
       return new WorkOrder(taskManager, workItem);
     } catch (exception, stackTrace) {
       throw new AnalysisException(
-          'Could not create work order (target = $target; result = $result)',
+          'Could not create work order (target = $target; taskDescriptor = $taskDescriptor; result = $result)',
           new CaughtException(exception, stackTrace));
     }
   }
 
   /**
    * Create a work order that will produce the required analysis results for
    * the given [target]. If [isPriority] is true, then the target is a priority
    * target. Return the work order that was created, or `null` if there is no
    * further work that needs to be done for the given target.
    */
@@ skipping 631 matching lines @@
   final TaskManager taskManager;
 
   _WorkOrderDependencyWalker(this.taskManager, WorkItem startingNode)
       : super(startingNode);
 
   @override
   WorkItem getNextInput(WorkItem node, List<WorkItem> skipInputs) {
     return node.gatherInputs(taskManager, skipInputs);
   }
 }