Bug 278553 – iframe's document not focusing when .focus() is called

• Component: WebCore Misc.
• Status: NEW

[Marcos Caceres]

There appears to be an issue with iframes not focusing when .focus() is called on them.

Test case:

```
window.onload = async function () {
    const iframes = document.querySelectorAll("iframe");
    
    for (let iframe of iframes) {
        await new Promise(resolve => {
            iframe.onload = resolve;
            iframe.src = "about:blank";
        });
        
        iframe.focus();
        console.assert(iframe.contentDocument.hasFocus(), "The iframe is not focused.");
    }
};
```

[Radar WebKit Bug Importer]

<rdar://problem/134992720>

[Marcos Caceres]

Test case https://jsfiddle.net/otg682h0/