### Issue Details
in frameless windows 
While setting browserview style to draggable by webkit-app-region : drag. the area won't be draggable after that
and it can not move main window 
### Electron Version:
11.0.1
### Operating System:
Windows 10 (1803)
Last Known Working Electron version:
not found
### Expected Behavior
Browser view moves the main window while I set the style of the body or one of the area to
-webkit-app-region: drag;

### Actual Behavior
nothing happen in browserview after styling -webkit-app-region: drag;

I know it is mention that in 11 version it is fixed. but it still dosn't work 

### To Reproduce
https://gist.github.com/pejmanpesyan/8540aad65e7c6980c45f23e5eaafafb9

shell/browser/native_browser_view_views.cc
#include "shell/browser/native_browser_view_views.h"
#include "shell/browser/ui/inspectable_web_contents_view.h"
#include "ui/gfx/geometry/rect.h"
#include "ui/views/background.h"
#include "ui/views/view.h"
namespace electron {
NativeBrowserViewViews::NativeBrowserViewViews(