Merge branch 'PHP-5.6' of git.php.net:php-src into PHP-5.6

* 'PHP-5.6' of git.php.net:php-src:
  removed outdated IsDebuggerPresent declaration
Fixed bug #66338 (Optimization binding of class constants is not safely opcacheable)
Merge branch 'PHP-5.6'

* PHP-5.6:
  Fixed bug #66338 (Optimization binding of class constants is not safely opcacheable)