WordPress: Add Google Font support to the Sage theme for roots.io

sage-google-fonts-config.php

<?php

/**
 * Add your Google Fonts here.
 * This is specifically for the theme Sage from roots.io and goes in config.php
 * Change the font name, weights and styles to what you are using as needed.
 */
define('GOOGLE_FONTS', 'Oswald:400,300,700:latin');

sage-google-fonts.php

<?php

/**
 * Manage google fonts of load_google_font()
 * This is specifically for the theme Sage from roots.io and goes in extras.php
 * set GOOGLE_FONTS constant in config.php
 */
function load_google_fonts() {

  if( ! defined( 'GOOGLE_FONTS' ) ) return;

  echo '<link href="https://fonts.googleapis.com/css?family=' . GOOGLE_FONTS . '" rel="stylesheet" type="text/css" />'."\n";
}
add_action( 'wp_head', __NAMESPACE__ . '\\load_google_fonts' , 1);