Disable HTTP tunneling support until the problem with delineation of 200 status message in response to CONNECT method has been resolved in HttpCore

git-svn-id: https://svn.apache.org/repos/asf/httpcomponents/httpclient/trunk@1794172 13f79535-47bb-0310-9956-ffa450edef68

httpclient5/src/main/java/org/apache/hc/client5/http/impl/async/InternalHttpAsyncClient.java

@@ -150,6 +150,11 @@ class InternalHttpAsyncClient extends AbstractHttpAsyncClientBase {
             log.debug(exchangeId + ": preparing request execution");
         }
 
+        //TODO remove when fixed in HttpCore
+        if (route.isTunnelled()) {
+            throw new HttpException("HTTP tunneling not supported");
+        }
+
         setupContext(clientContext);
 
         final AsyncExecChain.Scope scope = new AsyncExecChain.Scope(exchangeId, route, request, clientContext, execRuntime);