Drupal 7 HTML5 Minification

template.php

<?php

function THEMENAME_process_html(&$variables) {
  if (!empty($variables)) {
    $css_before = array(' type="text/css"', ' media="all"');
    $css_after = array('', '');

    $js_before = array(' type="text/javascript"', '<!--//--><![CDATA[//><!--', '//--><!]]>');
    $js_after = array('', '', '');

    $lines_two = "/\n\n/";
    $lines_one = "\n";

    $tags_before = array("/>\s\s+/", "/\s\s+</", "/>\t+</");
    $tags_after = array('> ', ' <', '> <');

    $text_before = array("/\s\s+(?=\w)/", "/(?<=\w)\s\s+/");
    $text_after = array(' ', ' ');

    // CSS files.
    $styles = drupal_get_css();
    $styles = str_replace($css_before, $css_after, $styles);
    $variables['styles'] = $styles;

    // JavaScript files.
    $scripts = drupal_get_js();
    $scripts = str_replace($js_before, $js_after, $scripts);
    $scripts = preg_replace($lines_two, $lines_one, $scripts);
    $variables['scripts'] = $scripts;

    // Page top.
    $page_top = $variables['page_top'];
    $page_top = preg_replace($text_before, $text_after, $page_top);
    $page_top = preg_replace($tags_before, $tags_after, $page_top);
    $variables['page_top'] = $page_top;

    // Page content.
    if (!preg_match('/<pre|<textarea/', $variables['page'])) {
      $page = $variables['page'];
      $page = preg_replace($text_before, $text_after, $page);
      $page = preg_replace($tags_before, $tags_after, $page);
      $variables['page'] = $page;
    }

    // Footer JavaScript files.
    $footer_js = drupal_get_js('footer');
    $footer_js = str_replace($js_before, $js_after, $footer_js);
    $footer_js = preg_replace($lines_two, $lines_one, $footer_js);

    // Page bottom.
    $page_bottom = $variables['page_bottom'];
    $page_bottom = preg_replace($text_before, $text_after, $page_bottom);
    $page_bottom = preg_replace($tags_before, $tags_after, $page_bottom);
    $variables['page_bottom'] = $page_bottom . $footer_js;
  }
}

I've updated the gist to reflect that boost in efficiency. Thanks! :)