Revert of [Reland] Scheduler refactoring to virtually eliminate redundant DoWorks

cc/test/ordered_simple_task_runner.h

Index: cc/test/ordered_simple_task_runner.h
diff --git a/cc/test/ordered_simple_task_runner.h b/cc/test/ordered_simple_task_runner.h
index 1ba8e950217897f6a61f897bd2f6f7a495a02f50..9620a96058df422e00c841a5512bca675422d9f0 100644
--- a/cc/test/ordered_simple_task_runner.h
+++ b/cc/test/ordered_simple_task_runner.h
@@ -130,9 +130,6 @@
   // Advance Now() to the next task to run.
   base::Callback<bool(void)> AdvanceNow();
 
-  // Removes all tasks whose weak pointer has been revoked.
-  void RemoveCancelledTasks();
-
  protected:
   static bool TaskRunCountBelowCallback(size_t max_tasks, size_t* task_run);
   bool TaskExistedInitiallyCallback(