Add support for Language method AnalyzeEntitySentiment (#426)

[core, language] Add support for Language method AnalyzeEntitySentiment

RestTrait.php

@@ -63,7 +63,14 @@ public function setRequestWrapper(RequestWrapper $requestWrapper)
      *
      * @param string $resource The resource type used for the request.
      * @param string $method The method used for the request.
-     * @param array $options [optional] Options used to build out the request.
+     * @param array $options [optional] {
+     *     Options used to build out the request.
+     *
+     *     @type RequestBuilder $requestBuilder An instance of RequestBuilder.
+     *           If provided, the request will be constructed using the given
+     *           instance, rather than the one found in the `$requestBuilder`
+     *           property.
+     * }
      * @return array
      */
     public function send($resource, $method, array $options = [])
@@ -74,9 +81,14 @@ public function send($resource, $method, array $options = [])
             'requestTimeout'
         ], $options);
 
+        $requestBuilder = $this->pluck('requestBuilder', $options, false);
+        if (is_null($requestBuilder) || !($requestBuilder instanceof RequestBuilder)) {
+            $requestBuilder = $this->requestBuilder;
+        }
+
         return json_decode(
             $this->requestWrapper->send(
-                $this->requestBuilder->build($resource, $method, $options),
+                $requestBuilder->build($resource, $method, $options),
                 $requestOptions
             )->getBody(),
             true