This bug was fixed in the package php-zeta-unit-test - 1.0.2-2ubuntu1
--------------- php-zeta-unit-test (1.0.2-2ubuntu1) xenial; urgency=medium
* Disable PNG mangling (LP: #1549046).
-- Nishanth Aravamudan <email address hidden> Tue, 23 Feb 2016 16:18:37 -0800
This bug was fixed in the package php-zeta-unit-test - 1.0.2-2ubuntu1
---------------
php-zeta-unit-test (1.0.2-2ubuntu1) xenial; urgency=medium
* Disable PNG mangling (LP: #1549046).
-- Nishanth Aravamudan <email address hidden> Tue, 23 Feb 2016 16:18:37 -0800