fix: disable title attribute on menu items (#4019)

Prevents a title attribute from being applied to MenuItems.
MenuItem indicates to ClickableComponent that the control is not just an icon, so it shouldn't have a title attribute.

Fixes #3699

src/js/clickable-component.js

@@ -121,7 +121,10 @@ class ClickableComponent extends Component {
 
     this.controlText_ = text;
     this.controlTextEl_.innerHTML = localizedText;
-    el.setAttribute('title', localizedText);
+    if (!this.nonIconControl) {
+      // Set title attribute if only an icon is shown
+      el.setAttribute('title', localizedText);
+    }
   }
 
   /**

src/js/menu/menu-item.js

@@ -54,6 +54,9 @@ class MenuItem extends ClickableComponent {
    *         The element that gets created.
    */
   createEl(type, props, attrs) {
+    // The control is textual, not just an icon
+    this.nonIconControl = true;
+
     return super.createEl('li', assign({
       className: 'vjs-menu-item',
       innerHTML: this.localize(this.options_.label),