LPS-49545

Hi @marcellustavares,

Based on https://github.com/marcellustavares/liferay-portal/pull/341 I've checked the tests and had to modify the code, and the test cases as well. 

Now I've tested the following scenarios with double parenthesis filters:
  * Import from LDAP after startup
  * Import User during login
  * Validate search and import filters on UI

There's one thing I changed significantly, the checking of the parenthesis pairs. I cut out everything else form the filter so only '(' and ')' remains and analyze it to see whether there are multiple pairs on the sam level.

Regards,
Vilmos