scheduler: Move the Blink scheduler into Blink

components/scheduler/child/single_thread_idle_task_runner.h

-// 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.
-
-#ifndef COMPONENTS_SCHEDULER_CHILD_SINGLE_THREAD_IDLE_TASK_RUNNER_H_
-#define COMPONENTS_SCHEDULER_CHILD_SINGLE_THREAD_IDLE_TASK_RUNNER_H_
-
-#include "base/bind.h"
-#include "base/callback.h"
-#include "base/macros.h"
-#include "base/memory/ref_counted.h"
-#include "base/single_thread_task_runner.h"
-#include "base/time/time.h"
-#include "base/trace_event/trace_event.h"
-#include "components/scheduler/scheduler_export.h"
-
-namespace base {
-namespace trace_event {
-class BlameContext;
-}
-}
-
-namespace scheduler {
-
-// A SingleThreadIdleTaskRunner is a task runner for running idle tasks. Idle
-// tasks have an unbound argument which is bound to a deadline
-// (in base::TimeTicks) when they are run. The idle task is expected to
-// complete by this deadline.
-class SingleThreadIdleTaskRunner
-    : public base::RefCountedThreadSafe<SingleThreadIdleTaskRunner> {
- public:
-  typedef base::Callback<void(base::TimeTicks)> IdleTask;
-
-  // Used to request idle task deadlines and signal posting of idle tasks.
-  class SCHEDULER_EXPORT Delegate {
-   public:
-    Delegate();
-    virtual ~Delegate();
-
-    // Signals that an idle task has been posted. This will be called on the
-    // posting thread, which may not be the same thread as the
-    // SingleThreadIdleTaskRunner runs on.
-    virtual void OnIdleTaskPosted() = 0;
-
-    // Signals that a new idle task is about to be run and returns the deadline
-    // for this idle task.
-    virtual base::TimeTicks WillProcessIdleTask() = 0;
-
-    // Signals that an idle task has finished being run.
-    virtual void DidProcessIdleTask() = 0;
-
-   private:
-    DISALLOW_COPY_AND_ASSIGN(Delegate);
-  };
-
-  // NOTE Category strings must have application lifetime (statics or
-  // literals). They may not include " chars.
-  SingleThreadIdleTaskRunner(
-      scoped_refptr<base::SingleThreadTaskRunner> idle_priority_task_runner,
-      scoped_refptr<base::SingleThreadTaskRunner> after_wakeup_task_runner,
-      Delegate* Delegate,
-      const char* tracing_category);
-
-  virtual void PostIdleTask(const tracked_objects::Location& from_here,
-                            const IdleTask& idle_task);
-
-  virtual void PostNonNestableIdleTask(
-      const tracked_objects::Location& from_here,
-      const IdleTask& idle_task);
-
-  virtual void PostIdleTaskAfterWakeup(
-      const tracked_objects::Location& from_here,
-      const IdleTask& idle_task);
-
-  bool RunsTasksOnCurrentThread() const;
-
-  void SetBlameContext(base::trace_event::BlameContext* blame_context);
-
- protected:
-  virtual ~SingleThreadIdleTaskRunner();
-
- private:
-  friend class base::RefCountedThreadSafe<SingleThreadIdleTaskRunner>;
-
-  void RunTask(IdleTask idle_task);
-
-  scoped_refptr<base::SingleThreadTaskRunner> idle_priority_task_runner_;
-  scoped_refptr<base::SingleThreadTaskRunner> after_wakeup_task_runner_;
-  Delegate* delegate_;  // NOT OWNED
-  const char* tracing_category_;
-  base::trace_event::BlameContext* blame_context_;  // Not owned.
-  base::WeakPtr<SingleThreadIdleTaskRunner> weak_scheduler_ptr_;
-  base::WeakPtrFactory<SingleThreadIdleTaskRunner> weak_factory_;
-  DISALLOW_COPY_AND_ASSIGN(SingleThreadIdleTaskRunner);
-};
-
-}  // namespace scheduler
-
-#endif  // COMPONENTS_SCHEDULER_CHILD_SINGLE_THREAD_IDLE_TASK_RUNNER_H_