[FIX] web_editor: restore 'title' attribute on 'we' element

Since a refactoring (it was working at some point), `title` attribute on `we`
elements would be lost when rendering actual DOM elements.

We had 2 occurences of `title` on `we` elements:
1. s_countdown > What Should Happ.. > Show Message > fa-eye icon has a title
   (in next version 13.2)
2. data-js `BackgroundPosition` (section) > fa-arrows has a title

Also, incoming Cookies Bar task/PR will add a title on 'Hide For' option.

closes odoo/odoo#43199

X-original-commit: 230a84edcea139bc7df44a4d1a27761e74038257
Signed-off-by: Quentin Smetz (qsm) <qsm@odoo.com>

addons/web_editor/static/src/js/editor/snippets.options.js

@@ -21,14 +21,19 @@ var _t = core._t;
  * @returns {HTMLElement} - the original 'el' argument
  */
 function _addTitleAndAllowedAttributes(el, title, options) {
+    let tooltipEl = el;
     if (title) {
         const titleEl = _buildTitleElement(title);
+        tooltipEl = titleEl;
         el.appendChild(titleEl);
     }
 
     if (options && options.classes) {
         el.classList.add(...options.classes);
     }
+    if (options && options.tooltip) {
+        tooltipEl.title = options.tooltip;
+    }
     if (options && options.dataAttributes) {
         for (const key in options.dataAttributes) {
             el.dataset[key] = options.dataAttributes[key];
@@ -1854,6 +1859,7 @@ const SnippetOptionWidget = Widget.extend({
             options: {
                 classes: el.classList,
                 dataAttributes: el.dataset,
+                tooltip: el.title,
                 childNodes: [...el.childNodes],
             },
         };