Create Mojo Struct for user information used in login/lock screen.

ash/public/interfaces/login_user_info.mojom

Index: ash/public/interfaces/login_user_info.mojom
diff --git a/ash/public/interfaces/login_user_info.mojom b/ash/public/interfaces/login_user_info.mojom
new file mode 100644
index 0000000000000000000000000000000000000000..d3274f9c0bc5133402246b36a45fd1ee2f432f7f
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+++ b/ash/public/interfaces/login_user_info.mojom
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+// Copyright 2017 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.
+
+module ash.mojom;
+
+import "ash/public/interfaces/user_info.mojom";
+import "mojo/common/string16.mojom";
+
+// Supported authentication types. Keep in sync with enum in
+// screenlock_bridge.h
+enum AuthType {
+  OFFLINE_PASSWORD,
+  ONLINE_SIGN_IN,
+  NUMERIC_PIN,
+  USER_CLICK,
+  EXPAND_THEN_USER_CLICK,
+  FORCE_OFFLINE_PASSWORD,
+};
+
+// Information about the custom icon in the user pod.
+struct UserPodCustomIconOptions {
+  string id;
+  mojo.common.mojom.String16 tooltip;
+  bool autoshow_tooltip;
+  mojo.common.mojom.String16 aria_label;
+  bool hardlock_on_click;
+  bool is_trial_run;
+};
+
+// Info about a user in login/lock screen. 
+struct LoginUserInfo {
+  UserInfo basic_user_info;
+  bool is_desktop_user;

[jdufault, 2017/06/13 17:41:54]

It'd be good to document all of these members, but especially is_desktop_user,
auth_type, is_multiprofile_allowed, and multiprofile_policy, since those are not
immediately obvious.

[xiaoyinh(OOO Sep 11-29), 2017/06/13 22:21:30]

Done.

+  AuthType auth_type;
+  bool is_signed_in;
+  bool is_owner;
+  bool allow_fingerprint_unlock;
+  bool is_multiprofile_allowed;
+  string multiprofile_policy;
+  bool can_remove;
+};