Changes for AsyncHttpClient#404

Author: rlubke

providers/grizzly/src/main/java/org/asynchttpclient/providers/grizzly/filters/ProxyFilter.java

@@ -81,9 +81,6 @@ public NextAction handleWrite(FilterChainContext ctx)
 
  private void addProxyHeaders(final Realm realm,
  final HttpRequestPacket request) {
- if (!request.getHeaders().contains(Header.ProxyConnection)) {
- request.setHeader(Header.ProxyConnection, "keep-alive");
- }
  if (realm != null && realm.getUsePreemptiveAuth()) {
  final String authHeaderValue = generateAuthHeader(realm);
  if (authHeaderValue != null) {