Merge pull request facebookarchive#798 from Nyholm/patch-1

Fixed build on HHVM

Author: yguedidi

.travis.yml

@@ -4,14 +4,18 @@ php:
   - 5.6
   - 7.0
   - 7.1
-  - hhvm
 
 sudo: false
 
 cache:
   directories:
     - $HOME/.composer/cache
 
+matrix:
+  include:
+    - php: hhvm
+      dist: trusty
+
 before_install:
   - travis_retry composer self-update