Will be nice to clear auth credentials. For example, I'm using a proxy that accepts options via username:

```
proxy.com:8080
user: wiliam_country_US
```

So, if I want to change the peer node, I change my username:

```
proxy.com:8080
user: wiliam_country_GB
```

But, I'm not changing the proxy, so electron has valid credentials and is not going to trigger `login` event.

I'm searching the way to clean auth settings so electron asks them again.
atom/browser/net/atom_url_request.cc
DCHECK_CURRENTLY_ON(content::BrowserThread::IO);
  request_.reset();
  if (request_context_getter_) {
    request_context_getter_->RemoveObserver(this);
    request_context_getter_ = nullptr;
  }
}
bool AtomURLRequest::Write(scoped_refptr<const net::IOBufferWithSize> buffer,
                           bool is_last) {
  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
  return content::BrowserThread::PostTask(
      content::BrowserThread::IO, FROM_HERE,
      base::Bind(&AtomURLRequest::DoWriteBuffer, this, buffer, is_last));
}
void AtomURLRequest::SetChunkedUpload(bool is_chunked_upload) {