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/api/atom_api_session.cc
const GURL& url) {
    DCHECK_CURRENTLY_ON(content::BrowserThread::IO);
    net::ProxyService* proxy_service =
        context_getter->GetURLRequestContext()->proxy_service();
    net::CompletionCallback completion_callback =
        base::Bind(&ResolveProxyHelper::OnResolveProxyCompleted,
                   base::Unretained(this));
    
    int result = proxy_service->ResolveProxy(
        url, "GET", net::LOAD_NORMAL, &proxy_info_, completion_callback,
        &pac_req_, nullptr, net::BoundNetLog());
    
    if (result != net::ERR_IO_PENDING)
      completion_callback.Run(result);
  }
  Session::ResolveProxyCallback callback_;
  net::ProxyInfo proxy_info_;
  net::ProxyService::PacRequest* pac_req_;
  scoped_refptr<base::SingleThreadTaskRunner> original_thread_;
  DISALLOW_COPY_AND_ASSIGN(ResolveProxyHelper);
};
template<typename ...T>
void RunCallbackInUI(const base::Callback<void(T...)>& callback, T... result) {