chore: fix xvfb in travis config, patch safari karma launchers

.travis.yml

@@ -4,8 +4,6 @@ cache: npm
 before_install:
   - npm install -g greenkeeper-lockfile@1
 before_script:
-  - export DISPLAY=:99.0
-  - sh -e /etc/init.d/xvfb start
   - greenkeeper-lockfile-update
 after_script: greenkeeper-lockfile-upload
 after_failure:
@@ -14,6 +12,8 @@ after_success:
   - npm run assets
 addons:
   chrome: stable
+services:
+  - xvfb
 
 env:
   global:

package.json

@@ -67,6 +67,7 @@
     "docs:fix": "remark --output -- './{,!(node_modules)/**/}!(CHANGELOG)*.md'",
     "docs:lang": "node build/translations.js",
     "netlify": "babel-node ./build/netlify-docs.js",
+    "prepare": "patch-package",
     "prepublishOnly": "run-p build",
     "publish": "node build/gh-release.js",
     "version": "node build/version.js && git add CHANGELOG.md",
@@ -123,6 +124,7 @@
     "node-sass": "^4.10.0",
     "npm-merge-driver-install": "^1.1.1",
     "npm-run-all": "^4.1.5",
+    "patch-package": "^5.1.1",
     "postcss-cli": "^6.0.1",
     "proxyquireify": "^3.2.1",
     "qunit": "~2.9.1",

patches/karma-safari-launcher+1.0.0.patch

@@ -0,0 +1,15 @@
+patch-package
+--- a/node_modules/karma-safari-launcher/index.js
++++ b/node_modules/karma-safari-launcher/index.js
+@@ -13,6 +13,11 @@ var SafariBrowser = function(baseBrowserDecorator) {
+       var content = data.toString().replace('%URL%', url);
+       var staticHtmlPath = self._tempDir + '/redirect.html';
+
++      var pathForMojave = path.join(process.env.HOME, 'Library/Containers/com.apple.Safari/Data/redirect.html');
++      if (fs.existsSync(pathForMojave)) {
++        staticHtmlPath = pathForMojave;
++      }
++
+       fs.writeFile(staticHtmlPath, content, function(err) {
+         self._execCommand(self._getCommand(), [staticHtmlPath]);
+       });

patches/karma-safaritechpreview-launcher+0.0.6.patch

@@ -0,0 +1,18 @@
+patch-package
+--- a/node_modules/karma-safaritechpreview-launcher/index.js
++++ b/node_modules/karma-safaritechpreview-launcher/index.js
+@@ -25,7 +25,13 @@ const SafariTechPreviewBrowser = function (baseBrowserDecorator) {
+       throw err;
+     }
+     const content = data.toString().replace('%URL%', url);
+-    const staticHtmlPath = self._tempDir + '/redirect.html';
++    var staticHtmlPath = self._tempDir + '/redirect.html';
++
++    var pathForMojave = path.join(process.env.HOME, 'Library/Containers/com.apple.SafariTechnologyPreview/Data/redirect.html');
++    if (fs.existsSync(pathForMojave)) {
++      staticHtmlPath = pathForMojave;
++    }
++
+     try {
+       yield fs.writeFile(staticHtmlPath, content);
+     } catch (err) {