Added AddDownload communication path and observers

chrome/browser/background_fetch/background_fetch_client_impl.cc

Index: chrome/browser/background_fetch/background_fetch_client_impl.cc
diff --git a/chrome/browser/background_fetch/background_fetch_client_impl.cc b/chrome/browser/background_fetch/background_fetch_client_impl.cc
index ae1cef10842c192251d0a538b4c239882a75446b..273fcd01f80a76385d7ec2ae7c6a2439a4ddff22 100644
--- a/chrome/browser/background_fetch/background_fetch_client_impl.cc
+++ b/chrome/browser/background_fetch/background_fetch_client_impl.cc
@@ -60,6 +60,39 @@ void BackgroundFetchClientImpl::Shutdown() {
 void BackgroundFetchClientImpl::SetDelegate(
     content::BackgroundFetchClient::Delegate* delegate) {
   delegate_ = delegate;
+
+  // If there are any previously registered observers, notify them now.
+  for (auto& observer : observers_)
+    observer.OnItemsAvailable(this);
+}
+
+void BackgroundFetchClientImpl::AddDownload(const GURL& url,
+                                            const std::string& registration_id,
+                                            const std::string& title,
+                                            int64_t total_download_size) {
+  // Construct an OfflineItem to pass to the Observers.
+  OfflineItem item(ContentId(namespace_, registration_id));
+  item.title = title;
+  item.is_transient = true;
+  item.total_size_bytes = total_download_size;
+  item.is_openable = false;
+  // Set the origin of the service worker as the url for attribution.
+  item.page_url = url;
+  item.is_off_the_record = profile_->IsOffTheRecord();
+  item.state = offline_items_collection::OfflineItemState::IN_PROGRESS;
+  item.is_resumable = true;
+  item.allow_metered = false;
+  item.received_bytes = 0;
+  item.percent_completed = 0;
+  item.time_remaining_ms = -1;
+  // TODO(harkness): Should BackgroundFetch set a description or filter?
+  // TODO(harkness): Should BackgroundFetch expose creation/access times?
+
+  OfflineContentProvider::OfflineItemList added_items;

[Peter Beverloo, 2017/04/24 14:39:15]

; -> {item};

+  added_items.push_back(item);
+
+  for (auto& observer : observers_)
+    observer.OnItemsAdded(added_items);
 }
 
 void BackgroundFetchClientImpl::CancelDownload(const ContentId& content_id) {
@@ -102,15 +135,25 @@ void BackgroundFetchClientImpl::GetVisualsForItem(
 }
 
 void BackgroundFetchClientImpl::AddObserver(Observer* observer) {
-  // TODO(harkness): Add a path for the OfflineContentProvider to observe
-  // changes in available BackgroundFetch items.
+  DCHECK(observer);
+  observers_.AddObserver(observer);
+
+  // If the Delegate has been set then it is assumed to be ready for queries.
+  if (delegate_)
+    observer->OnItemsAvailable(this);

[David Trainor- moved to gerrit, 2017/04/25 03:24:43]

Could we post this?

 }
 
-void BackgroundFetchClientImpl::RemoveObserver(Observer* observer) {}
+void BackgroundFetchClientImpl::RemoveObserver(Observer* observer) {
+  DCHECK(observer);
+  if (!observers_.HasObserver(observer))
+    return;
+
+  observers_.RemoveObserver(observer);
+}
 
 bool BackgroundFetchClientImpl::AreItemsAvailable() {
-  // TODO(harkness): Follow up with dtrainor about what action to take for this.
-  return false;
+  // If there is a delegate, it is assumed to be ready for query.
+  return delegate_;
 }
 
 void BackgroundFetchClientImpl::RemoveItem(const ContentId& content_id) {