Adds a flag to support "Virtual Time" to the blink scheduler

components/scheduler/child/virtual_time_tqm_delegate.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 COMPONENTS_SCHEDULER_CHILD_SCHEDULER_TASK_RUNNER_DELEGATE_IMPL_H_
-#define COMPONENTS_SCHEDULER_CHILD_SCHEDULER_TASK_RUNNER_DELEGATE_IMPL_H_
+#ifndef COMPONENTS_SCHEDULER_CHILD_VIRTUAL_TIME_TQM_DELEGATE_H_
+#define COMPONENTS_SCHEDULER_CHILD_VIRTUAL_TIME_TQM_DELEGATE_H_
 
+#include <map>
+
+#include "base/macros.h"
 #include "base/message_loop/message_loop.h"
-#include "components/scheduler/child/scheduler_task_runner_delegate.h"
+#include "base/time/tick_clock.h"
+#include "components/scheduler/child/scheduler_tqm_delegate.h"
 #include "components/scheduler/scheduler_export.h"
 
 namespace scheduler {
 
-class SCHEDULER_EXPORT SchedulerTaskRunnerDelegateImpl
-    : public SchedulerTaskRunnerDelegate {
+class SCHEDULER_EXPORT VirtualTimeTqmDelegate : public SchedulerTqmDelegate {
  public:
   // |message_loop| is not owned and must outlive the lifetime of this object.
-  static scoped_refptr<SchedulerTaskRunnerDelegateImpl> Create(
-      base::MessageLoop* message_loop);
+  static scoped_refptr<VirtualTimeTqmDelegate> Create(
+      base::MessageLoop* message_loop,
+      base::TimeTicks initial_now);
 
-  // SchedulerTaskRunnerDelegate implementation
+  // SchedulerTqmDelegate implementation
   void SetDefaultTaskRunner(
       scoped_refptr<base::SingleThreadTaskRunner> task_runner) override;
   void RestoreDefaultTaskRunner() override;
   bool PostDelayedTask(const tracked_objects::Location& from_here,
                        const base::Closure& task,
                        base::TimeDelta delay) override;
   bool PostNonNestableDelayedTask(const tracked_objects::Location& from_here,
                                   const base::Closure& task,
                                   base::TimeDelta delay) override;
   bool RunsTasksOnCurrentThread() const override;
   bool IsNested() const override;
+  base::TimeTicks NowTicks() override;
+  void OnNoMoreImmediateWork() override;
 
  protected:
-  ~SchedulerTaskRunnerDelegateImpl() override;
+  ~VirtualTimeTqmDelegate() override;
 
  private:
-  explicit SchedulerTaskRunnerDelegateImpl(base::MessageLoop* message_loop);
+  explicit VirtualTimeTqmDelegate(base::MessageLoop* message_loop,
+                                  base::TimeTicks initial_no);
+
+  void AdvancedTimeTo(base::TimeTicks now);
+
+  typedef std::multimap<base::TimeTicks, base::Closure> DelayedWakeupMultimap;
+
+  DelayedWakeupMultimap delayed_wakeup_multimap_;
 
   // Not owned.
   base::MessageLoop* message_loop_;
   scoped_refptr<SingleThreadTaskRunner> message_loop_task_runner_;
+  base::TimeTicks now_;
 
-  DISALLOW_COPY_AND_ASSIGN(SchedulerTaskRunnerDelegateImpl);
+  DISALLOW_COPY_AND_ASSIGN(VirtualTimeTqmDelegate);
 };
 
 }  // namespace scheduler
 
-#endif  // COMPONENTS_SCHEDULER_CHILD_SCHEDULER_TASK_RUNNER_DELEGATE_IMPL_H_
+#endif  // COMPONENTS_SCHEDULER_CHILD_VIRTUAL_TIME_TQM_DELEGATE_H_