### 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
auto* iwc_view = GetInspectableWebContentsView();
  if (!iwc_view)
    return;
  auto* view = iwc_view->GetView();
  view->SetBoundsRect(bounds);
  ResetAutoResizeProportions();
}
gfx::Rect NativeBrowserViewViews::GetBounds() {
  auto* iwc_view = GetInspectableWebContentsView();
  if (!iwc_view)
    return gfx::Rect();
  return iwc_view->GetView()->bounds();
}
void NativeBrowserViewViews::SetBackgroundColor(SkColor color) {
  auto* iwc_view = GetInspectableWebContentsView();
  if (!iwc_view)
    return;
  auto* view = iwc_view->GetView();
  view->SetBackground(views::CreateSolidBackground(color));
  view->SchedulePaint();
}
NativeBrowserView* NativeBrowserView::Create(
    InspectableWebContents* inspectable_web_contents) {
  return new NativeBrowserViewViews(inspectable_web_contents);
}
}