* **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.cc
if (content_view_.IsEmpty())
    return v8::Null(isolate());
  else
    return v8::Local<v8::Value>::New(isolate(), content_view_);
}
v8::Local<v8::Value> TopLevelWindow::GetParentWindow() const {
  if (parent_window_.IsEmpty())
    return v8::Null(isolate());
  else
    return v8::Local<v8::Value>::New(isolate(), parent_window_);
}
std::vector<v8::Local<v8::Object>> TopLevelWindow::GetChildWindows() const {
  return child_windows_.Values(isolate());
}
v8::Local<v8::Value> TopLevelWindow::GetBrowserView(
    mate::Arguments* args) const {
  if (browser_views_.size() == 0) {
    return v8::Null(isolate());
  } else if (browser_views_.size() == 1) {
    auto first_view = browser_views_.begin();
    return v8::Local<v8::Value>::New(isolate(), (*first_view).second);
  } else {
    args->ThrowError(
        "BrowserWindow have multiple BrowserViews, "
        "Use getBrowserViews() instead");
    return v8::Null(isolate());
  }
}
std::vector<v8::Local<v8::Value>> TopLevelWindow::GetBrowserViews() const {