Upgrade node version (flutter#9549)

mit-mit · web-flow · commit 2e10f61c5cec · 2017-04-24T13:14:44.000+02:00
* Upgrade node version

* Upgrade node version, but no further than 6 which is in LTS
diff --git a/.travis.yml b/.travis.yml
@@ -9,6 +9,9 @@ addons:
     packages:
       - libstdc++6
       - fonts-droid
+language: node_js
+node_js:
+  - "6"
 install:
   - ./dev/bots/travis_install.sh
 env:
