LibWeb: Make factory method of DOM::HTMLCollection fallible

Author: https://github.com/kennethmyhra
Commit: ff875d353b
Pull-request: https://github.com/SerenityOS/serenity/pull/17491
Reviewed-by: https://github.com/linusg ✅

Userland/Libraries/LibWeb/HTML/HTMLTableRowElement.cpp

@@ -45,7 +45,7 @@ JS::NonnullGCPtr<DOM::HTMLCollection> HTMLTableRowElement::cells() const
         m_cells = DOM::HTMLCollection::create(const_cast<HTMLTableRowElement&>(*this), [this](Element const& element) {
             return element.parent() == this
                 && is<HTMLTableCellElement>(element);
-        });
+        }).release_value_but_fixme_should_propagate_errors();
     }
     return *m_cells;
 }