Sanity check role before adding caps

reset-wp-civicrm-roles-caps.php

@@ -257,6 +257,11 @@ class CiviCRM_Permissions_Sync {
 		// Get the role to apply all CiviCRM permissions to.
 		$custom_role = $this->role_get();
 
+		// Bail if something went wrong.
+		if ( empty( $custom_role ) ) {
+			return;
+		}
+
 		// Add the capabilities if not already added.
 		foreach( $capabilities as $capability ) {
 			if ( ! $custom_role->has_cap( $capability ) ) {