Make travis build 7.2 with the old version of phpunit.

Author: ghalse

.travis.yml

@@ -12,6 +12,9 @@ matrix:
   - php: 7.2
   - php: hhvm
 
-before_script: composer update --dev
+before_script:
+  - composer update
+  - if [[ "$TRAVIS_PHP_VERSION" == "7.2" ]]; then echo 'error_reporting = E_ALL & ~E_DEPRECATED & ~E_STRICT' >> ~/.phpenv/versions/$(phpenv version-name)/etc/conf.d/travis.ini; fi
+
 script: php vendor/phpunit/phpunit/phpunit