Setting as default

I got the following error when I installed corolla 7.x-1.17, made my default theme went to the home page and back to appearance tab.

Warning: preg_replace(): Compilation failed: unrecognized character after (? at offset 9 in drupal_load_stylesheet_content() (line 3502 of /home/seth/april_2/includes/common.inc).

Here is the code it is referring to:

line 3487        $contents = preg_replace('<
       3488            (?|
       3489          # Strip leading and trailing whitespace.
       3490               \s*([@{};,])\s*
       3491          # Strip only leading whitespace from:
       3492          # - Closing parenthesis: Retain "@media (bar) and foo".
       3493           | \s+([\)])
       3494          # Strip only trailing whitespace from:
       3495          # - Opening parenthesis: Retain "@media (bar) and foo".
       3496          # - Colon: Retain :pseudo-selectors.
       3497          | ([\(:])\s+
       3498          )
       3499     >xS',
       3500          '\1',
       3501         $contents
       3502     );
       3503     // End the file with a new line.
       3504     $contents .= "\n";