Add two more options for the --password-store switch

components/os_crypt/key_storage_util_linux.h

Index: components/os_crypt/key_storage_util_linux.h
diff --git a/components/os_crypt/key_storage_util_linux.h b/components/os_crypt/key_storage_util_linux.h
new file mode 100644
index 0000000000000000000000000000000000000000..d5c04b6e70b8e8a36be3be6c1d428276704a40e4
--- /dev/null
+++ b/components/os_crypt/key_storage_util_linux.h
@@ -0,0 +1,35 @@
+// 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.
+
+#ifndef COMPONENTS_OS_CRYPT_KEY_STORAGE_UTIL_LINUX_H_
+#define COMPONENTS_OS_CRYPT_KEY_STORAGE_UTIL_LINUX_H_
+
+#include <string>
+
+#include "base/nix/xdg_util.h"
+
+namespace os_crypt {
+
+// The supported Linux backends for storing passwords.
+enum class SelectedLinuxBackend {
+  DEFER,  // No selection
+  BASIC_TEXT,
+  GNOME_ANY,  // GNOME_KEYRING or GNOME_LIBSECRET, whichever is available.
+  GNOME_KEYRING,
+  GNOME_LIBSECRET,
+  KWALLET,
+  KWALLET5,
+};
+
+// Decide which backend to target. |type| is checked first. If it does not
+// match a supported backend, |desktop_env| will be used to decide.
+// TODO(crbug/571003): This is exposed as a utility only for password manager to
+// use. It should be merged into key_storage_linux, once no longer needed in
+// password manager.
+SelectedLinuxBackend SelectBackend(const std::string& type,
+                                   base::nix::DesktopEnvironment desktop_env);
+
+}  // namespace os_crypt
+
+#endif  // COMPONENTS_OS_CRYPT_KEY_STORAGE_UTIL_LINUX_H_