Move throttling of background timers into the renderer scheduler

components/scheduler/base/real_time_domain.h

Index: components/scheduler/base/real_time_domain.h
diff --git a/components/scheduler/base/real_time_domain.h b/components/scheduler/base/real_time_domain.h
index f382fad3f0830527953f9bc8971effe4368d2d40..82525637d66fce4e3783f0e37d237d7174c9ba13 100644
--- a/components/scheduler/base/real_time_domain.h
+++ b/components/scheduler/base/real_time_domain.h
@@ -17,6 +17,7 @@ class TaskQueueManagerDelegate;
 class SCHEDULER_EXPORT RealTimeDomain : public TimeDomain {
  public:
   RealTimeDomain();
+  ~RealTimeDomain() override;
 
   // TimeDomain implementation:
   LazyNow CreateLazyNow() override;
@@ -40,8 +41,6 @@ class SCHEDULER_EXPORT RealTimeDomain : public TimeDomain {
   base::Closure do_work_closure_;
   base::WeakPtrFactory<RealTimeDomain> weak_factory_;
 
-  ~RealTimeDomain() override;
-
   DISALLOW_COPY_AND_ASSIGN(RealTimeDomain);
 };