feat: add --disable-dev-shm-usage flag to headless

This flag solves some issues when running chrome headless inside
docker. For more details check this puppeteer issue where they discuss
adding the flag to the default options as well:

puppeteer/puppeteer#1834

index.js

@@ -167,7 +167,11 @@ ChromeBrowser.prototype = {
 ChromeBrowser.$inject = ['baseBrowserDecorator', 'args']
 
 function headlessGetOptions (url, args, parent) {
-  var mergedArgs = parent.call(this, url, args).concat(['--headless', '--disable-gpu'])
+  var mergedArgs = parent.call(this, url, args).concat([
+    '--headless',
+    '--disable-gpu',
+    '--disable-dev-shm-usage'
+  ])
 
   var isRemoteDebuggingFlag = function (flag) {
     return flag.indexOf('--remote-debugging-port=') !== -1

test/jsflags.spec.js

@@ -66,6 +66,7 @@ describe('headlessGetOptions', function () {
       '-incognito',
       '--headless',
       '--disable-gpu',
+      '--disable-dev-shm-usage',
       '--remote-debugging-port=9222'
     ])
   })
@@ -81,7 +82,8 @@ describe('headlessGetOptions', function () {
       '-incognito',
       '--remote-debugging-port=9333',
       '--headless',
-      '--disable-gpu'
+      '--disable-gpu',
+      '--disable-dev-shm-usage'
     ])
   })
 })