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### Issue Details

* **Electron Version:** 6.0.0-beta.13
* **Operating System:** Windows 10

### Expected Behavior

When calling `browserWindow.setAlwaysOnTop(true)`, I expect the `always-on-top-changed` event to be called with the boolean `isAlwaysOnTop` parameter set to `true`, and vice versa.

### Actual Behavior

I experience the opposite of above: When calling `browserWindow.setAlwaysOnTop(true)`, my `always-on-top-changed` handler is called with `false`, and vice versa.

### To Reproduce

I don't have any JS code to share and I'm not a JS dev (I use F# and compile to JS with Fable). I think the issue should be easy to reproduce though.
shell/browser/native_window_views.cc
#include "shell/browser/native_window_views.h"
#if defined(OS_WIN)
#include <wrl/client.h>
#endif
#include <memory>
#include <tuple>
#include <utility>
#include <vector>
#include "base/stl_util.h"
#include "base/strings/utf_string_conversions.h"
#include "content/public/browser/browser_thread.h"
#include "native_mate/dictionary.h"
#include "shell/browser/api/atom_api_web_contents.h"
#include "shell/browser/native_browser_view_views.h"
#include "shell/browser/ui/inspectable_web_contents.h"
#include "shell/browser/ui/inspectable_web_contents_view.h"
#include "shell/browser/ui/views/root_view.h"
#include "shell/browser/web_contents_preferences.h"
#include "shell/browser/web_view_manager.h"
#include "shell/browser/window_list.h"
#include "shell/common/atom_constants.h"
#include "shell/common/native_mate_converters/image_converter.h"
#include "shell/common/options_switches.h"
#include "ui/aura/window_tree_host.h"
#include "ui/base/hit_test.h"
#include "ui/gfx/image/image.h"