[FIX] web_editor: also check getComputedStyle in isBlock if other doc

There was a condition in the `isBlock` util meant to bypass
`getComputedStyle` in the case that a node was not in the DOM. Rather
than doing that however, it was bypassing it in every case where the
node was in a document that was different from that of the window.

closes odoo/odoo#142803

X-original-commit: 04a9e97603806cb21cd90d991c0f94a225c326c5
Signed-off-by: Quentin Smetz (qsm) <qsm@odoo.com>

addons/web_editor/static/src/js/editor/odoo-editor/src/utils/utils.js

@@ -1242,13 +1242,13 @@ export function isBlock(node) {
         return false;
     }
     // The node might not be in the DOM, in which case it has no CSS values.
-    if (window.document !== node.ownerDocument) {
+    if (!node.isConnected) {
         return blockTagNames.includes(tagName);
     }
     // We won't call `getComputedStyle` more than once per node.
     let style = computedStyles.get(node);
     if (!style) {
-        style = window.getComputedStyle(node);
+        style = node.ownerDocument.defaultView.getComputedStyle(node);
         computedStyles.set(node, style);
     }
     if (style.display) {