Add a general purpose facility for letting background tasks wait until

components/offline_pages/background/request_coordinator.cc

Index: components/offline_pages/background/request_coordinator.cc
diff --git a/components/offline_pages/background/request_coordinator.cc b/components/offline_pages/background/request_coordinator.cc
index c7a5bdab4f274b84c8c647530272c814905a27f1..ffbd5bf3e536aae3aa385063c6b18f1f45ffa8c0 100644
--- a/components/offline_pages/background/request_coordinator.cc
+++ b/components/offline_pages/background/request_coordinator.cc
@@ -74,11 +74,6 @@ void RequestCoordinator::UpdateRequestCallback(
 
 // Called by the request picker when a request has been picked.
 void RequestCoordinator::RequestPicked(const SavePageRequest& request) {
-  Scheduler::TriggerCondition conditions;
-
-  // Ensure that the scheduler has actively scheduled a task.
-  scheduler_->Schedule(conditions);
-
   // Send the request on to the offliner.
   SendRequestToOffliner(request);
 }
@@ -153,7 +148,6 @@ void RequestCoordinator::OfflinerDoneCallback(const SavePageRequest& request,
 
   // Start a request if we have time.
   TryNextRequest();
-
 }
 
 }  // namespace offline_pages