Description:
------------
If you run string "X X" through html_entity_decode then check its' length it returns 4 instead of 3.

PHP 5.3.x gives correct result.

PHP 5.4.x and 5.5.x give incorrect result.

Possibly the same problem with other HTML entities, such as » etc...

Test script:
---------------
<?php
echo 'strlen(a) = ' .strlen("X X") . "<br>\n";
echo 'strlen(b) = ' .strlen(html_entity_decode('X&nbsp;X')) . "<br>\n";
?>

Expected result:
----------------
strlen(a) = 3
strlen(b) = 3

Actual result:
--------------
strlen(a) = 3
strlen(b) = 4