[Offline Pages] Make prerenderer notify us of network progress.

chrome/browser/android/offline_pages/prerendering_offliner.h

Index: chrome/browser/android/offline_pages/prerendering_offliner.h
diff --git a/chrome/browser/android/offline_pages/prerendering_offliner.h b/chrome/browser/android/offline_pages/prerendering_offliner.h
index 45eca74c5270792822dd410b0433ee1ee0b222e6..783dc9fc2d4469d39a8ac02b84e1780463ff3eb5 100644
--- a/chrome/browser/android/offline_pages/prerendering_offliner.h
+++ b/chrome/browser/android/offline_pages/prerendering_offliner.h
@@ -57,6 +57,9 @@ class PrerenderingOffliner : public Offliner {
       const SavePageCallback& save_callback);
 
  private:
+  // Progress callback for PrerenderingLoader::LoadPage().
+  void OnNetworkProgress(const SavePageRequest& request, int64_t bytes);
+
   // Callback logic for PrerenderingLoader::LoadPage().
   void OnLoadPageDone(const SavePageRequest& request,
                       Offliner::RequestStatus load_status,