Throw exception if object is disabled.

includes/FeedsConfigurable.inc

@@ -77,13 +77,16 @@ abstract class FeedsConfigurable {
   }
 
   /**
-   * Determine whether this object is persistent. I. e. it is defined either
-   * in code or in the database.
+   * Determine whether this object is persistent and enabled. I. e. it is
+   * defined either in code or in the database and it is enabled.
    */
   public function existing() {
     if ($this->export_type == FEEDS_EXPORT_NONE) {
       throw new FeedsNotExistingException(t('Object is not persistent.'));
     }
+    if ($this->disabled) {
+      throw new FeedsNotExistingException(t('Object is disabled.'));
+    }
     return $this;
   }