Fix for #906 + fixed travis allow_failures

Author: ezimuel

.travis.yml

@@ -14,12 +14,12 @@ matrix:
   include:
     - php: 7.1
       env: ES_VERSION="7.0.0"
-
     - php: 7.2
       env: ES_VERSION="7.0.0"
-
     - php: 7.3
       env: ES_VERSION="7.0.0"
+    - php: 7.3
+      env: ES_VERSION="7.1.0"
   allow_failures:
     - php: 7.3
       env: ES_VERSION="7.1.0"

src/Elasticsearch/Client.php

@@ -1026,7 +1026,6 @@ public function scroll(array $params = [])
     {
         $scrollID = $this->extractArgument($params, 'scroll_id');
         $body = $this->extractArgument($params, 'body');
-        $scroll = $this->extractArgument($params, 'scroll');
 
         /**
  * @var callable $endpointBuilder