Adds an observer for the request coordinator.

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 bd82c99ef2af5ec477d697ce1199839d5e4ab8b6..510361bc4ab13d306e971f553febe1f75a0d4096 100644
--- a/components/offline_pages/background/request_coordinator.cc
+++ b/components/offline_pages/background/request_coordinator.cc
@@ -88,6 +88,7 @@ bool RequestCoordinator::SavePageLater(
   queue_->AddRequest(request,
                      base::Bind(&RequestCoordinator::AddRequestResultCallback,
                                 weak_ptr_factory_.GetWeakPtr()));
+  NotifyAvailable(client_id);
   return true;
 }
 void RequestCoordinator::GetQueuedRequests(
@@ -129,6 +130,8 @@ void RequestCoordinator::PauseRequests(
   queue_->PauseRequestsByClientId(
       client_ids, base::Bind(&RequestCoordinator::UpdateMultipleRequestCallback,
                              weak_ptr_factory_.GetWeakPtr()));
+  for(ClientId client_id : client_ids)
+    NotifyPaused(client_id);
 }
 
 void RequestCoordinator::ResumeRequests(
@@ -137,12 +140,13 @@ void RequestCoordinator::ResumeRequests(
       client_ids, base::Bind(&RequestCoordinator::UpdateMultipleRequestCallback,
                              weak_ptr_factory_.GetWeakPtr()));
   // TODO: Should we also schedule a task, in case there is not one scheduled?
+  for (ClientId client_id : client_ids)
+    NotifyAvailable(client_id);
 }
 
 void RequestCoordinator::AddRequestResultCallback(
     RequestQueue::AddRequestResult result,
     const SavePageRequest& request) {
-
   // Inform the scheduler that we have an outstanding task..
   scheduler_->Schedule(GetTriggerConditionsForUserRequest());
 }
@@ -316,21 +320,30 @@ void RequestCoordinator::OfflinerDoneCallback(const SavePageRequest& request,
                           base::Bind(&RequestCoordinator::UpdateRequestCallback,
                                      weak_ptr_factory_.GetWeakPtr(),
                                      updated_request.client_id()));
+    NotifyFailed(request.client_id());
 
-  } else if (status == Offliner::RequestStatus::SAVED ||
-             request.completed_attempt_count() + 1 >=
-                 policy_->GetMaxCompletedTries()) {
-    // Remove the request from the queue if it either succeeded or exceeded the
-    // max number of retries.  The +1 represents the request that just
-    // completed. Since we call MarkAttemptCompleted within the if branches,
-    // the completed_attempt_count has not yet been updated when we are checking
-    // the if condition.
+  } else if (status == Offliner::RequestStatus::SAVED) {
+    // Remove the request from the queue if it either succeeded.
+    std::vector<ClientId> client_ids;
+    client_ids.push_back(request.client_id());
+    queue_->RemoveRequestsByClientId(
+        client_ids,
+        base::Bind(&RequestCoordinator::UpdateRequestCallback,
+                   weak_ptr_factory_.GetWeakPtr(), request.client_id()));
+    NotifySucceeded(request.client_id());
+  } else if (request.completed_attempt_count() + 1 >=
+             policy_->GetMaxCompletedTries()) {
+    // Remove from the request queue if we exceeeded max retries. The +1
+    // represents the request that just completed. Since we call
+    // MarkAttemptCompleted within the if branches, the completed_attempt_count
+    // has not yet been updated when we are checking the if condition.
     std::vector<ClientId> client_ids;
     client_ids.push_back(request.client_id());
     queue_->RemoveRequestsByClientId(
         client_ids,
         base::Bind(&RequestCoordinator::UpdateRequestCallback,
                    weak_ptr_factory_.GetWeakPtr(), request.client_id()));
+    NotifyFailed(request.client_id());
   } else {
     // If we failed, but are not over the limit, update the request in the
     // queue.
@@ -340,6 +353,7 @@ void RequestCoordinator::OfflinerDoneCallback(const SavePageRequest& request,
                           base::Bind(&RequestCoordinator::UpdateRequestCallback,
                                      weak_ptr_factory_.GetWeakPtr(),
                                      updated_request.client_id()));
+    NotifyAvailable(request.client_id());
   }
 
   // Determine whether we might try another request in this
@@ -375,6 +389,39 @@ RequestCoordinator::GetTriggerConditionsForUserRequest() {
   return trigger_conditions;
 }
 
+void RequestCoordinator::AddObserver(Observer* observer) {
+  DCHECK(observer);
+  observers_.AddObserver(observer);
+}
+
+void RequestCoordinator::RemoveObserver(Observer* observer) {
+  observers_.RemoveObserver(observer);
+}
+
+void RequestCoordinator::NotifyAvailable(ClientId client_id) {
+  RequestInfo info;
+  info.client_id = client_id;
+  FOR_EACH_OBSERVER(Observer, observers_, OnAvailable(info));
+}
+
+void RequestCoordinator::NotifySucceeded(ClientId client_id) {
+  RequestInfo info;
+  info.client_id = client_id;;
+  FOR_EACH_OBSERVER(Observer, observers_, OnSucceeded(info));
+}
+
+void RequestCoordinator::NotifyFailed(ClientId client_id) {
+  RequestInfo info;
+  info.client_id = client_id;
+  FOR_EACH_OBSERVER(Observer, observers_, OnFailed(info));
+}
+
+void RequestCoordinator::NotifyPaused(ClientId client_id) {
+  RequestInfo info;
+  info.client_id = client_id;
+  FOR_EACH_OBSERVER(Observer, observers_, OnPaused(info));
+}
+
 void RequestCoordinator::GetOffliner() {
   if (!offliner_) {
     offliner_ = factory_->GetOffliner(policy_.get());