chromeos: Remove "error_libcros_missing" error from file browser private API

chrome/common/extensions/api/file_browser_private.json

 // 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.
 
 [
   {
     "namespace":"fileBrowserPrivate",
     "nodoc": "true",
     "types": [
       {
@@ skipping 248 matching lines @@
         "properties": {
           "eventType": {
             "type": "string",
             "enum": ["mount", "unmount"],
             "description": "Is the event raised for mounting or unmounting."
           },
           "status": {
             "type": "string",
             "enum": ["success", "error_unknown", "error_internal",
                      "error_unknown_filesystem", "error_unsuported_filesystem",
-                     "error_invalid_archive", "error_libcros_missing",
-                     "error_authentication", "error_network",
-                     "error_path_unmounted"],
+                     "error_invalid_archive", "error_authentication",
+                     "error_network", "error_path_unmounted"],
             "description": "Event type that tells listeners if mount was successful or an error occurred. It also specifies the error."
           },
           "sourcePath": {
             "type": "string",
             "description": "Path that has been mounted."
           },
           "mountPath": {
             "type": "string",
             "optional": true,
             "description": "Path that sourcePath was mounted to."
@@ skipping 777 matching lines @@
       },
       {
         "name": "onNetworkConnectionChanged",
         "type": "function",
         "description": "Fired when the active network connection state changes. The network connection state can be retrieved via 'getNetworkConnectionState'.",
         "parameters": []
       }
     ]
   }
 ]