BUG #15056: restore error

The following bug has been logged on the website:

Bug reference:      15056
Logged by:          heemin.kim
Email address:      siarta@naver.com
PostgreSQL version: 10.1
Operating system:   win10,64bit
Description:

My restore job failed with below error log... and it apeared same as
restoring with other backup files.

#error log#
---------------------------------------
2018-02-09 16:11:07,099: ERROR    pgadmin:    object of type 'bool' has no len()
Traceback (most recent call last):
  File "C:\Program Files\PostgreSQL\10\pgAdmin
4\web\pgadmin\tools\restore\__init__.py", line 327, in create_restore_job
    *args
  File "C:\Program Files\PostgreSQL\10\pgAdmin
4\web\pgadmin\tools\restore\__init__.py", line 83, in __init__
    if arg and len(arg) >= 2 and arg[:2] == '--':
TypeError: object of type 'bool' has no len()
----------------------------------------

Thank you.