[Offline pages]: Implement background loader to save on last retry, and record last retry success U…

chrome/browser/android/offline_pages/prerendering_offliner.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/android/offline_pages/prerendering_offliner.h"
 
 #include "base/bind.h"
 #include "base/metrics/histogram_macros.h"
 #include "base/sys_info.h"
 #include "chrome/browser/android/offline_pages/offline_page_mhtml_archiver.h"
@@ skipping 140 matching lines @@
 
   // Clear pending request and app listener here and then inform loader we
   // are done with WebContents.
   pending_request_.reset(nullptr);
   app_listener_.reset(nullptr);
   GetOrCreateLoader()->StopLoading();
 
   // Determine status and run the completion callback.
   Offliner::RequestStatus save_status;
   if (save_result == SavePageResult::SUCCESS) {
-    save_status = RequestStatus::SAVED;
+    if (saved_on_last_retry_)

[Pete Williamson, 2017/04/13 22:57:15]

Should we clear this in the ctor just for completeness?

[fgorski, 2017/04/14 05:15:57]

If by clear you mean initialize: +1
... And Cathy knows how much debugging that takes to find.

[chili, 2017/04/15 00:34:59]

Done.
This actually caused a test failure T___T

+      save_status = RequestStatus::SAVED_ON_LAST_RETRY;
+    else
+      save_status = RequestStatus::SAVED;
   } else {
     // TODO(dougarnett): Consider reflecting some recommendation to retry the
     // request based on specific save error cases.
     save_status = RequestStatus::SAVE_FAILED;
   }
+  saved_on_last_retry_ = false;
   completion_callback_.Run(request, save_status);
 }
 
 bool PrerenderingOffliner::LoadAndSave(
     const SavePageRequest& request,
     const CompletionCallback& completion_callback,
     const ProgressCallback& progress_callback) {
   DCHECK(!pending_request_.get());
 
   if (pending_request_) {
@@ skipping 84 matching lines @@
   callback.Run(request_id);
 }
 
 bool PrerenderingOffliner::HandleTimeout(const SavePageRequest& request) {
   if (pending_request_) {
     DCHECK(request.request_id() == pending_request_->request_id());
     if (GetOrCreateLoader()->IsLowbarMet() &&
         (request.started_attempt_count() + 1 >= policy_->GetMaxStartedTries() ||
          request.completed_attempt_count() + 1 >=
              policy_->GetMaxCompletedTries())) {
+      saved_on_last_retry_ = true;
       GetOrCreateLoader()->StartSnapshot();
       return true;
     }
   }
   return false;
 }
 
 void PrerenderingOffliner::SetLoaderForTesting(
     std::unique_ptr<PrerenderingLoader> loader) {
   DCHECK(!loader_);
@@ skipping 42 matching lines @@
 void PrerenderingOffliner::HandleApplicationStateChangeCancel(
     const SavePageRequest& request,
     int64_t offline_id) {
   // This shouldn't be immediate, but account for case where request was reset
   // while waiting for callback.
   if (pending_request_ && pending_request_->request_id() != offline_id)
     return;
   completion_callback_.Run(request, RequestStatus::FOREGROUND_CANCELED);
 }
 }  // namespace offline_pages