Commit a new download to history db immediately on Android

components/history/core/browser/history_backend.cc

 // Copyright (c) 2012 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 "components/history/core/browser/history_backend.h"
 
 #include <algorithm>
 #include <functional>
 #include <list>
 #include <map>
@@ skipping 1161 matching lines @@
   if (!db_)
     return;
   db_->UpdateDownload(data);
   ScheduleCommit();
 }
 
 bool HistoryBackend::CreateDownload(const DownloadRow& history_info) {
   if (!db_)
     return false;
   bool success = db_->CreateDownload(history_info);
+#if defined(OS_ANDROID)
+  // On android, browser process can get easily killed. Download will no longer
+  // be able to resume and the temporary file will linger forever if the
+  // download is not committed before that. Do the commit right away to avoid
+  // uncommitted download entry before browser kill.

[sky, 2016/08/30 03:21:21]

'before browser kill' -> 'if browser is killed'

[qinmin, 2016/08/30 16:31:32]

Done.

+  Commit();
+#else
   ScheduleCommit();
+#endif
   return success;
 }
 
 void HistoryBackend::RemoveDownloads(const std::set<uint32_t>& ids) {
   if (!db_)
     return;
   size_t downloads_count_before = db_->CountDownloads();
   base::TimeTicks started_removing = base::TimeTicks::Now();
   // HistoryBackend uses a long-running Transaction that is committed
   // periodically, so this loop doesn't actually hit the disk too hard.
@@ skipping 1436 matching lines @@
   // transaction is currently open.
   db_->CommitTransaction();
   db_->Vacuum();
   db_->BeginTransaction();
   db_->GetStartDate(&first_recorded_time_);
 
   return true;
 }
 
 }  // namespace history