ChannelManager#updatePipelineForHttpTunneling doesn't position handlers properly wrt additionalChannelInitializer, close AsyncHttpClient#1529

Motivation: 030e3dd introduced a regression where ChannelManager#updatePipelineForHttpTunneling uses `addFirst` to set handlers in the pipeline. But additionalChannelInitializer might have set handlers that require to be in front of the pipeline. Modification: Set position relative to AHC handler. Result: Proper handler positions

Author: slandelle

client/src/main/java/org/asynchttpclient/netty/channel/ChannelManager.java

@@ -338,16 +338,15 @@ public void updatePipelineForHttpTunneling(ChannelPipeline pipeline, Uri request
  if (pipeline.get(HTTP_CLIENT_CODEC) != null)
  pipeline.remove(HTTP_CLIENT_CODEC);
 
- if (requestUri.isSecured())
- if (isSslHandlerConfigured(pipeline)) {
- pipeline.addAfter(SSL_HANDLER, HTTP_CLIENT_CODEC, newHttpClientCodec());
- } else {
- pipeline.addFirst(HTTP_CLIENT_CODEC, newHttpClientCodec());
- pipeline.addFirst(SSL_HANDLER, createSslHandler(requestUri.getHost(), requestUri.getExplicitPort()));
+ if (requestUri.isSecured()) {
+ if (!isSslHandlerConfigured(pipeline)) {
+ pipeline.addBefore(AHC_HTTP_HANDLER, SSL_HANDLER, createSslHandler(requestUri.getHost(), requestUri.getExplicitPort()));
  }
+ pipeline.addAfter(SSL_HANDLER, HTTP_CLIENT_CODEC, newHttpClientCodec());
 
- else
- pipeline.addFirst(HTTP_CLIENT_CODEC, newHttpClientCodec());
+ } else {
+ pipeline.addBefore(AHC_HTTP_HANDLER, HTTP_CLIENT_CODEC, newHttpClientCodec());
+ }
 
  if (requestUri.isWebSocket()) {
  pipeline.addAfter(AHC_HTTP_HANDLER, AHC_WS_HANDLER, wsHandler);