Fix the Download Notifications for Offline Pages to indicate bytes loaded.

components/offline_pages/core/downloads/download_notifying_observer.cc

Index: components/offline_pages/core/downloads/download_notifying_observer.cc
diff --git a/components/offline_pages/core/downloads/download_notifying_observer.cc b/components/offline_pages/core/downloads/download_notifying_observer.cc
index cca7406a97dd23b3dccc1d1fb5ffdb527109bc22..3783608812919c0e4d552a013c512ed46c4621eb 100644
--- a/components/offline_pages/core/downloads/download_notifying_observer.cc
+++ b/components/offline_pages/core/downloads/download_notifying_observer.cc
@@ -64,6 +64,14 @@ void DownloadNotifyingObserver::OnChanged(const SavePageRequest& request) {
   NotifyRequestStateChange(request);
 }
 
+void DownloadNotifyingObserver::OnNetworkProgress(
+    const SavePageRequest& request,
+    int64_t received_bytes) {
+  DownloadUIItem item(request);
+  item.download_progress_bytes = received_bytes;
+  notifier_->NotifyDownloadProgress(item);
+}
+
 void DownloadNotifyingObserver::OnCompleted(
     const SavePageRequest& request,
     RequestCoordinator::BackgroundSavePageResult status) {