Fix HTTPS protocol detection

Fix HTTPS protocol detection

According to PHP documentation:
http://www.php.net/manual/en/reserved.variables.server.php
The $_SERVER['HTTPS'] is set to a non-empty value if the script was queried
through the HTTPS protocol. There is also note that for ISAPI with IIS, the
value is set to 'off' if the request was not made through the HTTPS protocol.

To follow the PHP documentation the $_SERVER['HTTPS'] == 'on' doesn't seem
to be the correct way how to detect the HTTPS protocol (there maybe e.g. '1'
instead of 'on').

Bug: 46511
Change-Id: I5675fed9b7d54711b96b25702181112ef3692f3c