WP_REST_Themes_Controller::get_items

	public function get_items( $request ) {
		// Retrieve the list of registered collection query parameters.
		$registered = $this->get_collection_params();
		$themes     = array();

		if ( isset( $registered['status'], $request['status'] ) && in_array( 'active', $request['status'], true ) ) {
			$active_theme = wp_get_theme();
			$active_theme = $this->prepare_item_for_response( $active_theme, $request );
			$themes[]     = $this->prepare_response_for_collection( $active_theme );
		}

		$response = rest_ensure_response( $themes );

		$response->header( 'X-WP-Total', count( $themes ) );
		$response->header( 'X-WP-TotalPages', count( $themes ) );

		return $response;
	}