* Output of `node_modules/.bin/electron --version`: 2.0.0
* Operating System (Platform and Version): Windows 10

**Expected Behavior**
When I disable a window twice via `setEnabled(false)`, I expect the second disable to have no effect.

**Actual behavior**
The second disable is "queued" up, such that I am forced to enable the window twice to get back to normal.

**To Reproduce**
In the electronquickstart repo, in main.js' `createWindow()`, add these lines:

    mainWindow.setEnabled(false);
    mainWindow.setEnabled(false);
    mainWindow.setEnabled(true);

The window will be disabled when launched. 

You see the same issue if you do it in reverse:

    mainWindow.setEnabled(true);
    mainWindow.setEnabled(false); // this doesn't actually disable it, because the window was enabled from the getgo

If this is expected behavior, can the [docs](https://github.com/electron/electron/blob/master/docs/api/browser-window.md#winsetenabledenable) be updated to explain this behavior.
atom/browser/native_window_views.cc
#endif
  if (has_frame()) {
    
    
    widget()->set_frame_type(views::Widget::FrameType::FRAME_TYPE_FORCE_NATIVE);
    widget()->FrameTypeChanged();
#if defined(OS_WIN)
    
    if (!thick_frame_)
      FlipWindowStyle(GetAcceleratedWidget(), false, WS_THICKFRAME);
#endif
  }
  
  SetContentView(new views::View());
  gfx::Size size = bounds.size();
  if (has_frame() &&
      options.Get(options::kUseContentSize, &use_content_size_) &&
      use_content_size_)
    size = ContentBoundsToWindowBounds(gfx::Rect(size)).size();
  widget()->CenterWindow(size);
#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() {