Revert of scheduler: Implement task observers

content/renderer/scheduler/renderer_scheduler_impl.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/renderer/scheduler/renderer_scheduler_impl.h"
 
 #include "base/bind.h"
 #include "base/message_loop/message_loop_proxy.h"
 #include "base/trace_event/trace_event.h"
 #include "base/trace_event/trace_event_argument.h"
@@ skipping 428 matching lines @@
       // With no observable effect, these meta events do not indicate a
       // meaningful touchstart response and should not impact task priority.
       return current_state;
 
     default:
       break;
   }
   return INPUT_ACTIVE;
 }
 
-void RendererSchedulerImpl::AddTaskObserver(
-    base::MessageLoop::TaskObserver* task_observer) {
-  DCHECK(main_thread_checker_.CalledOnValidThread());
-  task_queue_manager_->AddTaskObserver(task_observer);
-}
-
-void RendererSchedulerImpl::RemoveTaskObserver(
-    base::MessageLoop::TaskObserver* task_observer) {
-  DCHECK(main_thread_checker_.CalledOnValidThread());
-  task_queue_manager_->RemoveTaskObserver(task_observer);
-}
-
 }  // namespace content