Update travis script and karma configuration to get tests working on …

…travis

See https://swizec.com/blog/how-to-run-javascript-tests-in-chrome-on-travis/swizec/6647 and karma-runner/karma#1144

.travis.yml

@@ -5,6 +5,11 @@ node_js:
 addons:
   chrome: stable
 
+before_install:
+  - export CHROME_BIN=chromium-browser
+  - export DISPLAY=:99.0
+  - sh -e /etc/init.d/xvfb start
+
 branches:
   only:
     - master

karma.conf.js

@@ -2,7 +2,8 @@
 // https://karma-runner.github.io/1.0/config/configuration-file.html
 
 module.exports = function (config) {
-  config.set({
+  // Our karma configuration
+  const configuration = {
     basePath: '',
     frameworks: ['jasmine', '@angular/cli'],
     plugins: [
@@ -28,6 +29,18 @@ module.exports = function (config) {
     logLevel: config.LOG_INFO,
     autoWatch: true,
     browsers: ['Chrome'],
-    singleRun: false
-  });
+    singleRun: false,
+    customLaunchers: {
+      Chrome_travis_ci: {
+        base: 'Chrome',
+        flags: ['--no-sandbox']
+      }
+    }
+  }
+
+  if(process.env.TRAVIS) {
+    configuration.browsers = ['Chrome_travis_ci'];
+  }
+
+  config.set(configuration);
 };