multi: fix streamclose() crash in debug mode

The code would refer to the wrong data pointer. Only debug builds do
this - for verbosity.

Reported-by: zelinchen@users.noreply.github.com
Fixes #1329

lib/multi.c

@@ -5,7 +5,7 @@
  *                            | (__| |_| |  _ <| |___
  *                             \___|\___/|_| \_\_____|
  *
- * Copyright (C) 1998 - 2016, Daniel Stenberg, <daniel@haxx.se>, et al.
+ * Copyright (C) 1998 - 2017, Daniel Stenberg, <daniel@haxx.se>, et al.
  *
  * This software is licensed as described in the file COPYING, which
  * you should have received as part of this distribution. The terms
@@ -695,13 +695,13 @@ CURLMcode curl_multi_remove_handle(struct Curl_multi *multi,
   if(data->easy_conn &&
      data->mstate > CURLM_STATE_DO &&
      data->mstate < CURLM_STATE_COMPLETED) {
+    /* Set connection owner so that the DONE function closes it.  We can
+       safely do this here since connection is killed. */
+    data->easy_conn->data = easy;
     /* If the handle is in a pipeline and has started sending off its
        request but not received its response yet, we need to close
        connection. */
     streamclose(data->easy_conn, "Removed with partial response");
-    /* Set connection owner so that the DONE function closes it.  We can
-       safely do this here since connection is killed. */
-    data->easy_conn->data = easy;
     easy_owns_conn = TRUE;
   }