* **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/api/atom_api_top_level_window.h
void SetMinimizable(bool minimizable);
  bool IsMinimizable();
  void SetMaximizable(bool maximizable);
  bool IsMaximizable();
  void SetFullScreenable(bool fullscreenable);
  bool IsFullScreenable();
  void SetClosable(bool closable);
  bool IsClosable();
  void SetAlwaysOnTop(bool top, mate::Arguments* args);
  bool IsAlwaysOnTop();
  void Center();
  void SetPosition(int x, int y, mate::Arguments* args);
  std::vector<int> GetPosition();
  void SetTitle(const std::string& title);
  std::string GetTitle();
  void FlashFrame(bool flash);
  void SetSkipTaskbar(bool skip);
  void SetSimpleFullScreen(bool simple_fullscreen);
  bool IsSimpleFullScreen();
  void SetKiosk(bool kiosk);
  bool IsKiosk();
  virtual void SetBackgroundColor(const std::string& color_name);
  void SetHasShadow(bool has_shadow);
  bool HasShadow();
  void SetOpacity(const double opacity);
  double GetOpacity();
  void SetShape(const std::vector<gfx::Rect>& rects);
  void SetRepresentedFilename(const std::string& filename);
  std::string GetRepresentedFilename();
  void SetDocumentEdited(bool edited);