[sync] Add backup time in synced device info so that server can flag device

sync/internal_api/sync_db_util.cc

+// Copyright 2014 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 "sync/internal_api/public/util/sync_db_util.h"
+
+#include "base/files/file_path.h"
+#include "base/single_thread_task_runner.h"
+#include "sql/connection.h"
+#include "sync/syncable/directory.h"
+
+namespace syncer {
+
+void CheckSyncDbLastModifiedTime(
+    const base::FilePath& sync_dir,
+    scoped_refptr<base::SingleThreadTaskRunner> callback_runner,
+    base::Callback<void(base::Time)> callback) {
+  const base::FilePath sync_db =
+      sync_dir.Append(syncable::Directory::kSyncDatabaseFilename);
+
+  base::File f(sync_db, base::File::FLAG_OPEN | base::File::FLAG_READ);
+  base::File::Info info;
+  if (!f.IsValid() || !f.GetInfo(&info)) {
+    callback_runner->PostTask(FROM_HERE, base::Bind(callback, base::Time()));
+    return;
+  }
+  f.Close();
+
+  sql::Connection db;
+  if (!db.Open(sync_db) || !db.QuickIntegrityCheck()) {
+    callback_runner->PostTask(FROM_HERE, base::Bind(callback, base::Time()));
+  } else {
+    callback_runner->PostTask(FROM_HERE,
+                              base::Bind(callback, info.last_modified));
+  }
+}
+
+}  // namespace syncer