Split the RequestPicker task into two separate tasks.

components/offline_pages/background/request_coordinator.h

Index: components/offline_pages/background/request_coordinator.h
diff --git a/components/offline_pages/background/request_coordinator.h b/components/offline_pages/background/request_coordinator.h
index 8b07e33a3efd9017698225b30fcfa31586c755b2..eacc95c399be8afbec7f46faff5d362fc30b3bdf 100644
--- a/components/offline_pages/background/request_coordinator.h
+++ b/components/offline_pages/background/request_coordinator.h
@@ -270,12 +270,13 @@ class RequestCoordinator : public KeyedService,
   void ScheduleAsNeeded();
 
   // Callback from the request picker when it has chosen our next request.
-  void RequestPicked(const SavePageRequest& request);
+  void RequestPicked(const SavePageRequest& request, bool cleanup_needed);
 
   // Callback from the request picker when no more requests are in the queue.
   // The parameter is a signal for what (if any) conditions to schedule future
   // processing for.
-  void RequestNotPicked(bool non_user_requested_tasks_remaining);
+  void RequestNotPicked(bool non_user_requested_tasks_remaining,
+                        bool cleanup_needed);
 
   // Callback from request picker that receives the current available queued
   // request count as well as the total queued request count (which may be