* **Electron Version:**
  4.0.2
* **Operating System:**
  macOS 10.14.3
* **Last Known Working Electron version:**:
  1.7

### Expected Behavior
When creating a BrowserWindow it should not appear in the dock menu by defaults.

### Actual Behavior
It appears in the dock menu (example: `raven` in https://electronjs.org/docs/tutorial/macos-dock)

### To Reproduce
Just create new BrowserWindow, then right click on the app icon in the dock. (see https://electronjs.org/docs/tutorial/macos-dock)

At least it should be a way to control that, this can be achieve for top level window with:
`[window_ setExcludedFromWindowsMenu:YES];`, indeed [window isExcludedFromWindowsMenu] returns false by default, see

https://developer.apple.com/documentation/appkit/nsapplication/1428625-removewindowsitem
`Use the isExcludedFromWindowsMenu method of NSWindow if you want the item to remain excluded from the Window menu.`
https://developer.apple.com/documentation/appkit/nswindow/1419175-isexcludedfromwindowsmenu

atom/browser/native_window_views.cc
if (event->type() != ui::ET_MOUSE_PRESSED)
    return;
  if (event->changed_button_flags() == ui::EF_BACK_MOUSE_BUTTON)
    NotifyWindowExecuteAppCommand(kBrowserBackward);
  else if (event->changed_button_flags() == ui::EF_FORWARD_MOUSE_BUTTON)
    NotifyWindowExecuteAppCommand(kBrowserForward);
}
#endif
ui::WindowShowState NativeWindowViews::GetRestoredState() {
  if (IsMaximized())
    return ui::SHOW_STATE_MAXIMIZED;
  if (IsFullscreen())
    return ui::SHOW_STATE_FULLSCREEN;
  return ui::SHOW_STATE_NORMAL;
}
NativeWindow* NativeWindow::Create(const mate::Dictionary& options,
                                   NativeWindow* parent) {
  return new NativeWindowViews(options, parent);
}
}