[v4b, modal, bug] Right padding added even if there is no scroll bar to hide

Created by: zorgoz

Even if there is no scroll bar on body element to be hidden, an extra right padding is added when the dialog is shown. Look at the gap that appears between the green bar and the red rectangle in the reduced test case.

Environment:

• Windows 2016 x64
• Chrome 60.0.3112.101
• Reduced test case: https://jsbin.com/hurotibesi/edit?html,output