* Electron version: 1.6.0, does _not_ repro in 1.4.x
* Operating system: Win32 tested, others possible

It appears that even if you create a window with `focusable: false` and `show: false`, calling `loadURL` on it will cause it to accept window focus and for other windows to lose focus.

### How to reproduce

Open the default Electron app

```js
BW = require('electron').remote.BrowserWindow
let ourWindow = BW.getFocusedWindow()
ourWindow.on('blur', () => console.log("Lost it!"))

hidden = new BW({show: false, width: 500, height: 500, focusable: false})
hidden.loadURL("http://www.yahoo.com")

>>> "Lost it!"
```

This breaks anyone using background windows for computation such as VS Code and Slack (via electron-remote), because whenever a background task kicks off, users can't type anymore
atom/browser/native_window_views.cc
if (!thick_frame_)
    ex_style |= WS_EX_COMPOSITED;
  if (window_type == "toolbar")
    ex_style |= WS_EX_TOOLWINDOW;
  ::SetWindowLong(GetAcceleratedWidget(), GWL_EXSTYLE, ex_style);
#endif
  
  
  if (has_frame()) {
    window_->set_frame_type(views::Widget::FrameType::FRAME_TYPE_FORCE_NATIVE);
    window_->FrameTypeChanged();
  }
  gfx::Size size = bounds.size();
  if (has_frame() &&
      options.Get(options::kUseContentSize, &use_content_size_) &&
      use_content_size_)
    size = ContentBoundsToWindowBounds(gfx::Rect(size)).size();
  window_->CenterWindow(size);
  Layout();
#if defined(OS_WIN)
  
  if (fullscreen)
    last_window_state_ = ui::SHOW_STATE_FULLSCREEN;
  else
    last_window_state_ = ui::SHOW_STATE_NORMAL;
  last_normal_bounds_ = GetBounds();
#endif
}
NativeWindowViews::~NativeWindowViews() {