[scheduler] Implement time-based cpu throttling.

third_party/WebKit/Source/platform/scheduler/child/scheduler_helper.h

 // Copyright 2015 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.
 
 #ifndef THIRD_PARTY_WEBKIT_SOURCE_PLATFORM_SCHEDULER_CHILD_SCHEDULER_HELPER_H_
 #define THIRD_PARTY_WEBKIT_SOURCE_PLATFORM_SCHEDULER_CHILD_SCHEDULER_HELPER_H_
 
 #include <stddef.h>
 
 #include "base/macros.h"
@@ skipping 46 matching lines @@
   void RemoveTaskTimeObserver(TaskTimeObserver* task_time_observer);
 
   // Shuts down the scheduler by dropping any remaining pending work in the work
   // queues. After this call any work posted to the task runners will be
   // silently dropped.
   void Shutdown();
 
   // Returns true if Shutdown() has been called. Otherwise returns false.
   bool IsShutdown() const { return !task_queue_manager_.get(); }
 
-  void CheckOnValidThread() const {
+  inline void CheckOnValidThread() const {

[alex clarke (OOO till 29th), 2016/09/07 15:13:07]

Out of curiosity why was this needed? Did it actually make any difference in
practice?

[altimin, 2016/09/09 15:43:57]

I was thinking about calling CheckOnValidThread in TaskQueueThrottler, but I've
abandoned the idea (resulted in more complex and less readable code).

inline was added to avoid function call with empty contents in release mode
(most of compilers were doing this anyway, but I wanted to be sure).

     DCHECK(thread_checker_.CalledOnValidThread());
   }
 
   // Creates a new TaskQueue with the given |spec|.
   scoped_refptr<TaskQueue> NewTaskQueue(const TaskQueue::Spec& spec);
 
   class BLINK_PLATFORM_EXPORT Observer {
    public:
     virtual ~Observer() {}
 
@@ skipping 37 matching lines @@
   const char* tracing_category_;
   const char* disabled_by_default_tracing_category_;
 
   DISALLOW_COPY_AND_ASSIGN(SchedulerHelper);
 };
 
 }  // namespace scheduler
 }  // namespace blink
 
 #endif  // THIRD_PARTY_WEBKIT_SOURCE_PLATFORM_SCHEDULER_CHILD_SCHEDULER_HELPER_H_