Improve performance of HTMLHelepr include relative paths

[andrepereiradasilva]

Summary of Changes

Improve performance of include relartive path when php configuration uses open_basedir

Testing Instructions

1. Test performance, use open_basedir in your php config and put, for instance (try with other files, paths and parameters), in your template index.php.

use Joomla\CMS\HTML\HTMLHelper;

$timeStart = microtime(true);
HTMLHelper::_('image' , 'calendar.png', 'alternative text');
HTMLHelper::_('image' , 'joomla.png', 'alternative text');
HTMLHelper::_('image' , 'system/pdf_button.png', 'alternative text');
HTMLHelper::_('image' , 'media/uploading.png', 'alternative text');
HTMLHelper::_('image' , 'jui/ajax-loader.gif', 'alternative text');
HTMLHelper::_('image' , 'mod_languages/uk_ua.gif', 'alternative text');
HTMLHelper::_('script' , 'caption.js');
HTMLHelper::_('script' , 'system/validate.js');
HTMLHelper::_('script' , 'jui/jquery.min.js');
HTMLHelper::_('script' , 'plg_system_stats/stats.js');
HTMLHelper::_('script' , 'mod_sampledata/sampledata-process.js');
HTMLHelper::_('stylesheet' , 'template.css');
HTMLHelper::_('stylesheet' , 'system/frontediting.css');
HTMLHelper::_('stylesheet' , 'jui/bootstrap.min.css');
HTMLHelper::_('stylesheet' , 'plg_system_highlight/highlight.css');
HTMLHelper::_('stylesheet' , 'mod_languages/template.css');
echo number_format(((microtime(true) - $timeStart) * 1000), 3) . 'ms';

My results in php 7.1.x with open_basedir:

• Before: ~3.400ms
• After: ~1.500ms

More files loaded more savings.

2. Test if all the css, scripts and images still render fine.

3. Code review.

Documentation Changes Required

None.