### 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
if ((auto_resize_flags_ & AutoResizeFlags::kAutoResizeVertical) &&
      !auto_vertical_proportion_set_) {
    auto* iwc_view = GetInspectableWebContentsView();
    if (!iwc_view)
      return;
    auto* view = iwc_view->GetView();
    auto view_bounds = view->bounds();
    auto_vertical_proportion_height_ =
        static_cast<float>(window_size.height()) /
        static_cast<float>(view_bounds.height());
    auto_vertical_proportion_top_ = static_cast<float>(window_size.height()) /
                                    static_cast<float>(view_bounds.y());
    auto_vertical_proportion_set_ = true;
  }
}
void NativeBrowserViewViews::AutoResize(const gfx::Rect& new_window,
                                        int width_delta,
                                        int height_delta) {
  auto* iwc_view = GetInspectableWebContentsView();
  if (!iwc_view)
    return;
  auto* view = iwc_view->GetView();
  const auto flags = GetAutoResizeFlags();
  if (!(flags & kAutoResizeWidth)) {
    width_delta = 0;
  }
  if (!(flags & kAutoResizeHeight)) {
    height_delta = 0;
  }
  if (height_delta || width_delta) {