* 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/ui/views/root_view.cc
return menu_bar_autohide_;
}
void RootView::SetMenuBarVisibility(bool visible) {
  if (!window_->content_view() || !menu_bar_ || menu_bar_visible_ == visible)
    return;
  menu_bar_visible_ = visible;
  if (visible) {
    DCHECK_EQ(child_count(), 1);
    AddChildView(menu_bar_.get());
  } else {
    DCHECK_EQ(child_count(), 2);
    RemoveChildView(menu_bar_.get());
  }
  Layout();
}
bool RootView::IsMenuBarVisible() const {
  return menu_bar_visible_;
}
void RootView::HandleKeyEvent(const content::NativeWebKeyboardEvent& event) {
  if (!menu_bar_)
    return;
  
  if (menu_bar_visible_ && IsAltKey(event))
    menu_bar_->SetAcceleratorVisibility(event.GetType() ==
                                        blink::WebInputEvent::kRawKeyDown);
  
  if (event.GetType() == blink::WebInputEvent::kRawKeyDown &&
      !IsAltKey(event) && IsAltModifier(event)) {
    if (menu_bar_->HasAccelerator(event.windows_key_code)) {
      if (!menu_bar_visible_) {