arc: Add explicit error message in case network cannot be setup.

chrome/browser/chromeos/arc/arc_support_host.h

 // 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 CHROME_BROWSER_CHROMEOS_ARC_ARC_SUPPORT_HOST_H_
 #define CHROME_BROWSER_CHROMEOS_ARC_ARC_SUPPORT_HOST_H_
 
 #include <memory>
 #include <string>
 
@@ skipping 15 matching lines @@
   enum class UIPage {
     NO_PAGE,      // Hide everything.
     TERMS,        // Terms content page.
     LSO,          // LSO page to enter user's credentials.
     ARC_LOADING,  // ARC loading progress page.
     ERROR,        // ARC start error page.
   };
 
   // Error types whose corresponding message ARC support has.
   enum class Error {
     SIGN_IN_NETWORK_ERROR,

[Luis Héctor Chávez, 2017/03/21 21:22:22]

nit: Can these be sorted lexicographically?

[khmel, 2017/03/21 21:31:40]

Good point, thanks for review!

     SIGN_IN_SERVICE_UNAVAILABLE_ERROR,
     SIGN_IN_BAD_AUTHENTICATION_ERROR,
     SIGN_IN_GMS_NOT_AVAILABLE_ERROR,
     SIGN_IN_CLOUD_PROVISION_FLOW_FAIL_ERROR,
     SIGN_IN_UNKNOWN_ERROR,
     SERVER_COMMUNICATION_ERROR,
     ANDROID_MANAGEMENT_REQUIRED_ERROR,
+    NETWORK_UNAVAILABLE_ERROR,
   };
 
   // Observer to notify UI event.
   class Observer {
    public:
     virtual ~Observer() = default;
 
     // Called when the ARC support window is closed.
     virtual void OnWindowClosed() {}
 
@@ skipping 132 matching lines @@
   bool is_arc_managed_ = false;
 
   PreferenceCheckboxData metrics_checkbox_;
   PreferenceCheckboxData backup_and_restore_checkbox_;
   PreferenceCheckboxData location_services_checkbox_;
 
   DISALLOW_COPY_AND_ASSIGN(ArcSupportHost);
 };
 
 #endif  // CHROME_BROWSER_CHROMEOS_ARC_ARC_SUPPORT_HOST_H_