* Electron Version: 3.0.0-beta.1 ~ 3.0.0-beta.6
* Operating System (Platform and Version): Ubuntu 16.04.2 LTS
* Last known working Electron version: versions before 3.0.0-beta.1

**Expected Behavior**
Console prints out `time to print stuff` when `Ctrl+P` is pressed.
```
const {Menu, MenuItem} = require('electron')
const menu = new Menu()
  
app.on('ready', () => {
  createWindow()
  menu.append(new MenuItem({
    label: 'Print',
    accelerator: 'CmdOrCtrl+P',
    click: () => { console.log('time to print stuff') }
  }))
  Menu.setApplicationMenu(menu)
})
```
https://github.com/hackjutsu/electron-quick-start/commit/6ceb5d7dcd2d946c071b43a3fdd1b0434ddebff5
**Actual behavior**
No output. The accelerator event is not triggered.

**To Reproduce**
```sh
git clone https://github.com/hackjutsu/electron-quick-start
cd electron-quick-start
npm install
npm run start
```
Try pressing `Ctrl+P`, and observe the output. (nothing happen...)
Change the electron version back to 2.0.0 in `pakcage.json`
```sh
npm install
npm run start
```
Try pressing `Ctrl+P`, and observe the output. (the log `time to print stuff` will show up in console)

atom/browser/native_window_views.cc
#endif
namespace atom {
namespace {
#if defined(OS_WIN)
void FlipWindowStyle(HWND handle, bool on, DWORD flag) {
  DWORD style = ::GetWindowLong(handle, GWL_STYLE);
  if (on)
    style |= flag;
  else
    style &= ~flag;
  ::SetWindowLong(handle, GWL_STYLE, style);
}
#endif
class NativeWindowClientView : public views::ClientView {
 public:
  NativeWindowClientView(views::Widget* widget,
                         views::View* root_view,
                         NativeWindowViews* window)
      : views::ClientView(widget, root_view), window_(window) {}
  ~NativeWindowClientView() override = default;
  bool CanClose() override {
    window_->NotifyWindowCloseButtonClicked();
    return false;
  }
 private:
  NativeWindowViews* window_;
  DISALLOW_COPY_AND_ASSIGN(NativeWindowClientView);
};
}  
NativeWindowViews::NativeWindowViews(const mate::Dictionary& options,