title: QML MenuItem trigger by Enter and keyboard events forwarding don't work
body: <p>Here I have a minimal example:</p>
  
  <pre><code>import QtQuick 2.9
  import QtQuick.Controls 2.3
  import QtQuick.Window 2.2
  
  
  Window {
      visible: true
      width: 640
      height: 480
      title: qsTr("Hello World")
  
      Component.onCompleted: {
          menu.open();
      }
  
      Menu {
          id: menu
  
          Keys.onPressed: {
              console.log("pressed")
          }
  
          MenuItem {
              text: "test"
              Keys.forwardTo: [menu]
              focus: highlighted
              onTriggered: {
                  console.log("triggered 1")
              }
          }
          MenuItem {
              text: "test2"
              focus: highlighted
              Keys.forwardTo: [menu]
              onTriggered: {
                  console.log("triggered 2")
              }
          }
          MenuItem {
              text: "test3"
              focus: highlighted
              Keys.forwardTo: [menu]
              onTriggered: {
                  console.log("triggered 3")
              }
          }
  
      }
  
  }
  </code></pre>
  
  <p>Navigating through Menu Items with keyboard works as expected. But triggering with Enter key doesn't work. Also as a workaround I tried to forward key events to the parent menu item, and it didn't work as well.</p>
  
  <p>The only way to fix it I see right now: place <code>Keys.onReturnPressed</code> to every MenuItem and make it call triggered() signal. But it feels wrong.</p>
  
  <p>Is it a bug of Qt?
  What is a right workaround for it?</p>
  
  <p>I'm using Qt 5.10.1</p>