[FIX] website, *: properly clean website widgets

* web_editor

When an user saves its website, all the animations are destroyed so that
a clean DOM is saved. This is particularly important for snippets like
the latest post one that would crash the page if not cleaned before
saving.

Two cases were found where animations were not cleaned before saving and
this is what this commit fixes:
- When an user used the undo/redo system, all animations were lost as
  the DOM is recreated.
- When an user duplicated a snippet, animations were not restarted on
  the cloned element.

closes odoo/odoo#29159

addons/web_editor/static/src/js/editor/rte.js

@@ -42,7 +42,10 @@ var History = function History($editable) {
             $editable.removeAttr('contentEditable').removeProp('contentEditable');
         }
 
+        $editable.trigger('content_will_be_destroyed');
         $editable.html(oSnap.contents).scrollTop(oSnap.scrollTop);
+        $editable.trigger('content_was_recreated');
+
         $('.oe_overlay').remove();
         $('.note-control-selection').hide();
 
@@ -276,6 +279,20 @@ var RTEWidget = Widget.extend({
 
         var $editable = this.editable();
 
+        // When a undo/redo is performed, the whole DOM is changed so we have
+        // to prepare for it (website will restart animations for example)
+        // TODO should be better handled
+        $editable.on('content_will_be_destroyed', function (ev) {
+            self.trigger_up('content_will_be_destroyed', {
+                $target: $(ev.currentTarget),
+            });
+        });
+        $editable.on('content_was_recreated', function (ev) {
+            self.trigger_up('content_was_recreated', {
+                $target: $(ev.currentTarget),
+            });
+        });
+
         $editable.addClass('o_editable')
         .data('rte', this)
         .each(function () {

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

@@ -336,6 +336,7 @@ var SnippetEditor = Widget.extend({
                 }
             },
         });
+        this.trigger_up('snippet_cloned', {$target: $clone});
     },
     /**
      * Called when the overlay dimensions/positions should be recomputed.

addons/website/static/src/js/menu/edit.js

@@ -15,6 +15,9 @@ var EditPageMenu = websiteNavbarData.WebsiteNavbarActionWidget.extend({
         edit: '_startEditMode',
     }),
     custom_events: _.extend({}, websiteNavbarData.WebsiteNavbarActionWidget.custom_events || {}, {
+        content_will_be_destroyed: '_onContentWillBeDestroyed',
+        content_was_recreated: '_onContentWasRecreated',
+        snippet_cloned: '_onSnippetCloned',
         snippet_dropped: '_onSnippetDropped',
     }),
 
@@ -83,6 +86,44 @@ var EditPageMenu = websiteNavbarData.WebsiteNavbarActionWidget.extend({
     // Handlers
     //--------------------------------------------------------------------------
 
+    /**
+     * Called when content will be destroyed in the page. Notifies the
+     * WebsiteRoot that is should stop the animations.
+     *
+     * @private
+     * @param {OdooEvent} ev
+     */
+    _onContentWillBeDestroyed: function (ev) {
+        this.trigger_up('animation_stop_demand', {
+            $target: ev.data.$target,
+        });
+    },
+    /**
+     * Called when content will be recreated in the page. Notifies the
+     * WebsiteRoot that is should start the animations.
+     *
+     * @private
+     * @param {OdooEvent} ev
+     */
+    _onContentWasRecreated: function (ev) {
+        this.trigger_up('animation_start_demand', {
+            editableMode: true,
+            $target: ev.data.$target,
+        });
+    },
+    /**
+     * Called when a snippet is cloned in the page. Notifies the WebsiteRoot
+     * that is should start the animations for this snippet.
+     *
+     * @private
+     * @param {OdooEvent} ev
+     */
+    _onSnippetCloned: function (ev) {
+        this.trigger_up('animation_start_demand', {
+            editableMode: true,
+            $target: ev.data.$target,
+        });
+    },
     /**
      * Called when a snippet is dropped in the page. Notifies the WebsiteRoot
      * that is should start the animations for this snippet.