[FIX] web_editor, website: fix ignoring unapplied device invisibility

Upon drop, the fix in [1] did consider invisible the blocks that were
visible within the current preview mode (mobile/desktop).
Because of this `onTargetHide` was be called instead of `onTargetShow`.

This commit changes that behavior so that the correct method remains
called according to the actual visibility, but the `DeviceVisibility`'s
`onTargetShow` is adapted to only add the override if it matches the
current preview mode.

No steps to reproduce for this first change, but third-party options
could have been impacted by it.

This commit also adds that condition on the cleanup that was added in
[2] to keep the `dataset.invisible` state consistent upon toggling the
preview mode.

Steps to reproduce this second issue:
- Drop a Columns snippet.
- Make a column visible only on mobile.
- Make another column visible only on desktop.
- Toggle preview mode several times.

=> `dataset.invisible` was set to `1` on all columns having
device-dependent visibility.

[1]: https://github.com/odoo/odoo/commit/acfca25e48ac9bc227234de860fe8128f0312ed4
[2]: https://github.com/odoo/odoo/commit/174e9fe0d8665d1a81c90a6f7bf5cc9e3361f161

task-3538535

closes odoo/odoo#143640

closes odoo/odoo#143875

Signed-off-by: Arthur Detroux (ard) <ard@odoo.com>
Signed-off-by: Benoit Socias (bso) <bso@odoo.com>

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

@@ -896,10 +896,6 @@ var SnippetEditor = Widget.extend({
                 if (isMobilePreview === isMobileHidden) {
                     // Preview mode and hidden type are the same.
                     show = false;
-                } else {
-                    // Preview mode is not related to hidden type.
-                    delete this.$target[0].dataset.invisible;
-                    return false;
                 }
             }
         }
@@ -4473,9 +4469,15 @@ var SnippetsMenu = Widget.extend({
                 gridUtils._reloadLazyImages(gridItemEl);
             }
 
+            const isMobilePreview = weUtils.isMobileView(this.$body[0]);
             for (const invisibleOverrideEl of this.getEditableArea().find('.o_snippet_mobile_invisible, .o_snippet_desktop_invisible')) {
+                const isMobileHidden = invisibleOverrideEl.classList.contains("o_snippet_mobile_invisible");
                 invisibleOverrideEl.classList.remove('o_snippet_override_invisible');
-                invisibleOverrideEl.dataset.invisible = '1';
+                if (isMobilePreview === isMobileHidden) {
+                    invisibleOverrideEl.dataset.invisible = '1';
+                } else {
+                    delete invisibleOverrideEl.dataset.invisible;
+                }
             }
 
             // This is async but using the main editor mutex, currently locked.

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

@@ -2596,8 +2596,11 @@ options.registry.DeviceVisibility = options.Class.extend({
      * @override
      */
     async onTargetShow() {
-        if (this.$target[0].classList.contains('o_snippet_mobile_invisible')
-                || this.$target[0].classList.contains('o_snippet_desktop_invisible')) {
+        const isMobilePreview = weUtils.isMobileView(this.$target[0]);
+        const isMobileHidden = this.$target[0].classList.contains("o_snippet_mobile_invisible");
+        if ((this.$target[0].classList.contains('o_snippet_mobile_invisible')
+                || this.$target[0].classList.contains('o_snippet_desktop_invisible')
+            ) && isMobilePreview === isMobileHidden) {
             this.$target[0].classList.add('o_snippet_override_invisible');
         }
     },