Fixx HHVM coverage issue

Author: Márk Sági-Kazár

.travis.yml

@@ -28,7 +28,7 @@ matrix:
           env: COMPOSER_FLAGS="--prefer-stable --prefer-lowest" COVERAGE=true TEST_COMMAND="composer test-ci"
 
 before_install:
-    - if [[ $COVERAGE != true ]]; then phpenv config-rm xdebug.ini; fi
+    - if [[ $COVERAGE != true && $TRAVIS_PHP_VERSION != hhvm ]]; then phpenv config-rm xdebug.ini; fi
     - travis_retry composer self-update
 
 install: