[HttpClient] Declare $active first to prevent weird issue

Author: Kyra Farrow

CurlHttpClient.php

@@ -290,6 +290,7 @@ public function stream($responses, float $timeout = null): ResponseStreamInterfa
             throw new \TypeError(sprintf('%s() expects parameter 1 to be an iterable of CurlResponse objects, %s given.', __METHOD__, \is_object($responses) ? \get_class($responses) : \gettype($responses)));
         }
 
+        $active = 0;
         while (CURLM_CALL_MULTI_PERFORM === curl_multi_exec($this->multi->handle, $active));
 
         return new ResponseStream(CurlResponse::stream($responses, $timeout));
@@ -302,6 +303,7 @@ public function __destruct()
             curl_multi_setopt($this->multi->handle, CURLMOPT_PUSHFUNCTION, null);
         }
 
+        $active = 0;
         while (CURLM_CALL_MULTI_PERFORM === curl_multi_exec($this->multi->handle, $active));
 
         foreach ($this->multi->openHandles as $ch) {

Response/CurlResponse.php

@@ -255,6 +255,7 @@ private static function perform(CurlClientState $multi, array &$responses = null
 
         try {
             self::$performing = true;
+            $active = 0;
             while (CURLM_CALL_MULTI_PERFORM === curl_multi_exec($multi->handle, $active));
 
             while ($info = curl_multi_info_read($multi->handle)) {