[iOS] Add HistoryDatabaseParamsForPath in //components/history/ios/browser

components/history/ios/browser/history_database_helper.cc

 // Copyright 2015 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/content/browser/history_database_helper.h"
+#include "components/history/ios/browser/history_database_helper.h"
 
 #include "base/files/file_path.h"
-#include "components/history/content/browser/download_constants_utils.h"
 #include "components/history/core/browser/history_database_params.h"
-#include "content/public/browser/download_interrupt_reasons.h"
 
 namespace history {
+namespace {
+
+// The download successfully completed.
+const DownloadInterruptReason kDownloadInterruptReasonNone = 0;
+
+// The download was interrupted by a browser crash. Internal use only.

[droger, 2015/04/24 14:38:29]

1) What does "Internal use only" means?

2) Why are these values 0 and 50? If this is important, please explain where
they come from, or at least a comment telling to not change them.

+// Resume pending downloads if possible.
+const DownloadInterruptReason kDownloadInterruptReasonCrash = 50;
+
+}  // namespace
 
 HistoryDatabaseParams HistoryDatabaseParamsForPath(
     const base::FilePath& history_dir) {
   return HistoryDatabaseParams(
       history_dir,
-      history::ToHistoryDownloadInterruptReason(
-          content::DOWNLOAD_INTERRUPT_REASON_NONE),
-      history::ToHistoryDownloadInterruptReason(
-          content::DOWNLOAD_INTERRUPT_REASON_CRASH));
+      kDownloadInterruptReasonNone,
+      kDownloadInterruptReasonCrash);
 }
 
 }  // namespace