- Electron version: >=0.37
- Operating system: ubuntu linux x64

When server send header 'WWW-Authenticate: Negotiate' electron not send kerberos ticket. 
`app.allowNTLMCredentialsForAllDomains(true)`  is called.

On electron v0.36.x it work's fine.

atom/browser/api/atom_api_session.cc
net::ProxyConfig* out) {
    std::string proxy_rules;
    GURL pac_url;
    mate::Dictionary options;
    
    
    if (ConvertFromV8(isolate, val, &proxy_rules)) {
      pac_url = GURL(proxy_rules);  
    } else if (ConvertFromV8(isolate, val, &options)) {
      options.Get("pacScript", &pac_url);
      options.Get("proxyRules", &proxy_rules);
    } else {
      return false;
    }
    
    if (!pac_url.is_empty() && pac_url.is_valid()) {
      out->set_pac_url(pac_url);
    } else {
      out->proxy_rules().ParseFromString(proxy_rules);
    }
    return true;
  }
};
}  
namespace atom {
namespace api {
namespace {
using WrapSessionCallback = base::Callback<void(v8::Local<v8::Value>)>;
WrapSessionCallback g_wrap_session;
class ResolveProxyHelper {