[ticket/11762] Use the === operator to distinguish "0" from ""

PHPBB3-11762
[ticket/11762] Fixed test's filename

PHPBB3-11762
[ticket/11762] Added call to test class's parent::setUp().

Added call to test class's parent::setUp(). Updated copyright year.

PHPBB3-11762
Merge remote-tracking branch 's9e/ticket/11762' into develop-olympus

* s9e/ticket/11762:
  [ticket/11762] Added call to test class's parent::setUp().
  [ticket/11762] Fixed test's filename
  [ticket/11762] Use the === operator to distinguish "0" from ""