Issue #3492320: Provide a getter method for the views csv query plugin where property

Closes #3492320

src/Plugin/views/query/ViewsCsvQuery.php

@@ -74,7 +74,7 @@ class ViewsCsvQuery extends QueryPluginBase {
    *
    * @var array
    */
-  public $where = [];
+  public array $where = [];
 
   /**
    * A simple array of filter clauses.
@@ -493,6 +493,16 @@ class ViewsCsvQuery extends QueryPluginBase {
     ];
   }
 
+  /**
+   * Retrieves the conditions placed on this query.
+   *
+   * @return array
+   *   The conditions.
+   */
+  public function &getWhere(): array {
+    return $this->where;
+  }
+
   /**
    * To store the filter values required to pick the node from the csv.
    *