As in topic. API currently offers fixed ratio only for Mac but not for Windows
shell/browser/native_window_views.cc
}
    }
  }
#endif
  
  gfx::Size content_size = GetContentSize();
  bool should_reset_size = use_content_size_ && has_frame() &&
                           !IsMenuBarAutoHide() &&
                           ((!!menu_model) != root_view_->HasMenu());
  root_view_->SetMenu(menu_model);
  if (should_reset_size) {
    
    int menu_bar_height = root_view_->GetMenuBarHeight();
    extensions::SizeConstraints constraints = GetContentSizeConstraints();
    if (constraints.HasMinimumSize()) {
      gfx::Size min_size = constraints.GetMinimumSize();
      min_size.set_height(min_size.height() + menu_bar_height);
      constraints.set_minimum_size(min_size);
    }
    if (constraints.HasMaximumSize()) {
      gfx::Size max_size = constraints.GetMaximumSize();
      max_size.set_height(max_size.height() + menu_bar_height);
      constraints.set_maximum_size(max_size);
    }
    SetContentSizeConstraints(constraints);
    
    SetContentSize(content_size);
  }
}
void NativeWindowViews::AddBrowserView(NativeBrowserView* view) {