Make old task manager tests work against new task manager.

chrome/browser/ui/task_manager/task_manager_table_model.h

Index: chrome/browser/ui/task_manager/task_manager_table_model.h
diff --git a/chrome/browser/ui/task_manager/task_manager_table_model.h b/chrome/browser/ui/task_manager/task_manager_table_model.h
index bd175a9a6bc473a3829f4ee1b207ad57f075339e..068fa352a10f6ef3e76938823f70967c7bb6b409 100644
--- a/chrome/browser/ui/task_manager/task_manager_table_model.h
+++ b/chrome/browser/ui/task_manager/task_manager_table_model.h
@@ -101,6 +101,11 @@ class TaskManagerTableModel
   void ToggleColumnVisibility(int column_id);
 
  private:
+  friend class TaskManagerTesterImpl;
+
+  // Hook to let TaskManagerTesterImpl inspect the content of the task manager.
+  static TaskManagerTableModel* GetInstanceForTesting();
+
   // Start / stop observing the task manager.
   void StartUpdating();
   void StopUpdating();