fix chrome addon config for Travis

.travis.yml

@@ -1,4 +1,3 @@
-sudo: required
 dist: trusty
 language: node_js
 node_js:
@@ -8,22 +7,18 @@ env: # a separate build will start for each env
   - TEST_DIR=app
 
 addons:
-apt:
+  chrome: stable
-  sources:
-    - google-chrome
-  packages:
-    - google-chrome-stable
-    - google-chrome-beta
 
 before_install:
-  - export CHROME_BIN=chromium-browser
-  - export DISPLAY=:99.0
-  - sh -e /etc/init.d/xvfb start
   - cd $TEST_DIR # switch to the directory we're testing
   # npm install happens here
 
+before_script:
+  - export DISPLAY=:99.0
+  - sh -e /etc/init.d/xvfb start
+
 script:
-- npm run test-ci
+  - npm run test-ci
 
 after_success:
   - ./node_modules/.bin/codecov # Send coverage