Simplify fileBrowserPrivate.getDriveConnectionStatus().

chrome/browser/resources/file_manager/background/js/volume_manager.js

 // Copyright (c) 2012 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.
 
 'use strict';
 
 /**
  * Represents each volume, such as "drive", "download directory", each "USB
  * flush storage", or "mounted zip archive" etc.
  *
@@ skipping 315 matching lines @@
   /**
    * The list of VolumeInfo instances for each mounted volume.
    * @type {VolumeInfoList}
    */
   this.volumeInfoList = new VolumeInfoList();
 
   // The status should be merged into VolumeManager.
   // TODO(hidehiko): Remove them after the migration.
   this.driveConnectionState_ = {
     type: util.DriveConnectionType.OFFLINE,
-    reasons: [util.DriveConnectionReason.NO_SERVICE]
+    reason: util.DriveConnectionReason.NO_SERVICE
   };
 
   chrome.fileBrowserPrivate.onDriveConnectionStatusChanged.addListener(
       this.onDriveConnectionStatusChanged_.bind(this));
   this.onDriveConnectionStatusChanged_();
 }
 
 /**
  * Invoked when the drive connection status is changed.
  * @private_
@@ skipping 358 matching lines @@
       callbacks[i].apply(self, args);
     }
   };
   if (status === 'success') {
     callEach(request.successCallbacks, this, [opt_mountPath]);
   } else {
     volumeManagerUtil.validateError(status);
     callEach(request.errorCallbacks, this, [status]);
   }
 };