scheduler: Tell v8 about the current RAIL mode

content/test/fake_renderer_scheduler.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 CONTENT_TEST_FAKE_RENDERER_SCHEDULER_H_
 #define CONTENT_TEST_FAKE_RENDERER_SCHEDULER_H_
 
 #include "base/macros.h"
 #include "components/scheduler/renderer/renderer_scheduler.h"
 
@@ skipping 40 matching lines @@
   bool ShouldYieldForHighPriorityWork() override;
   void AddTaskObserver(base::MessageLoop::TaskObserver* task_observer) override;
   void RemoveTaskObserver(
       base::MessageLoop::TaskObserver* task_observer) override;
   void Shutdown() override;
   void SuspendTimerQueue() override;
   void ResumeTimerQueue() override;
   void SetTimerQueueSuspensionWhenBackgroundedEnabled(bool enabled) override;
   void SetTopLevelBlameContext(
       base::trace_event::BlameContext* blame_context) override;
+  void SetRAILModeObserver(RAILModeObserver* observer) override;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(FakeRendererScheduler);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_TEST_FAKE_RENDERER_SCHEDULER_H_