Replace PhantomJS with headless Chrome for Rspec tests

Closes #30876

.gitlab-ci.yml

-image: "dev.gitlab.org:5005/gitlab/gitlab-build-images:ruby-2.3.3-golang-1.8-git-2.7-phantomjs-2.1-node-7.1-postgresql-9.6"
+image: "dev.gitlab.org:5005/gitlab/gitlab-build-images:ruby-2.3.3-golang-1.8-git-2.7-chrome-59.0-node-7.1-postgresql-9.6"
 cache:
   key: "ruby-233-with-yarn"

Gemfile

@@ -325,7 +325,7 @@ group :development, :test do
   gem 'capybara', '~> 2.6.2'
   gem 'capybara-screenshot', '~> 1.0.0'
-  gem 'poltergeist', '~> 1.9.0'
+  gem 'selenium-webdriver', '~> 2.53'
   gem 'spring', '~> 2.0.0'
   gem 'spring-commands-rspec', '~> 1.0.4'

Gemfile.lock

@@ -114,12 +114,13 @@ GEM
       mime-types (>= 1.16)
     cause (0.1)
     charlock_holmes (0.7.3)
+    childprocess (0.7.0)
+      ffi (~> 1.0, >= 1.0.11)
     chronic (0.10.2)
     chronic_duration (0.10.6)
       numerizer (~> 0.1.1)
     chunky_png (1.3.5)
     citrus (3.0.2)
-    cliver (0.3.2)
     coderay (1.1.1)
     coercible (1.0.0)
       descendants_tracker (~> 0.0.1)
@@ -584,11 +585,6 @@ GEM
     pg (0.18.4)
     po_to_json (1.0.1)
       json (>= 1.6.0)
-    poltergeist (1.9.0)
-      capybara (~> 2.1)
-      cliver (~> 0.3.1)
-      multi_json (~> 1.0)
-      websocket-driver (>= 0.2.0)
     posix-spawn (0.3.11)
     powerpack (0.1.1)
     premailer (1.8.6)
@@ -769,6 +765,10 @@ GEM
       activesupport (>= 3.1)
     select2-rails (3.5.9.3)
       thor (~> 0.14)
+    selenium-webdriver (2.53.4)
+      childprocess (~> 0.5)
+      rubyzip (~> 1.0)
+      websocket (~> 1.0)
     sentry-raven (2.4.0)
       faraday (>= 0.7.6, < 1.0)
     settingslogic (2.0.9)
@@ -891,9 +891,7 @@ GEM
       hashdiff
     webpack-rails (0.9.10)
       railties (>= 3.2.0)
-    websocket-driver (0.6.3)
-      websocket-extensions (>= 0.1.0)
-    websocket-extensions (0.1.2)
+    websocket (1.2.4)
     wikicloth (0.8.1)
       builder
       expression_parser
@@ -1042,7 +1040,6 @@ DEPENDENCIES
   peek-redis (~> 1.2.0)
   peek-sidekiq (~> 1.0.3)
   pg (~> 0.18.2)
-  poltergeist (~> 1.9.0)
   premailer-rails (~> 1.9.0)
   prometheus-client-mmap (~> 0.7.0.beta5)
   pry-byebug (~> 3.4.1)
@@ -1081,6 +1078,7 @@ DEPENDENCIES
   scss_lint (~> 0.47.0)
   seed-fu (~> 2.3.5)
   select2-rails (~> 3.5.9)
+  selenium-webdriver (~> 2.53)
   sentry-raven (~> 2.4.0)
   settingslogic (~> 2.0.9)
   sham_rack (~> 1.3.6)

features/support/capybara.rb

-require 'capybara/poltergeist'
 require 'capybara-screenshot/spinach'
 # Give CI some extra time
 timeout = (ENV['CI'] || ENV['CI_SERVER']) ? 60 : 30
-Capybara.javascript_driver = :poltergeist
-Capybara.register_driver :poltergeist do |app|
-  Capybara::Poltergeist::Driver.new(
-    app,
-    js_errors: true,
-    timeout: timeout,
-    window_size: [1366, 768],
-    url_whitelist: %w[localhost 127.0.0.1],
-    url_blacklist: %w[.mp4 .png .gif .avi .bmp .jpg .jpeg],
-    phantomjs_options: [
-      '--load-images=yes'
-    ]
+Capybara.javascript_driver = :chrome
+Capybara.register_driver :chrome do |app|
+  capabilities = Selenium::WebDriver::Remote::Capabilities.chrome(
+    'chromeOptions' => {
+      'args' => %w[headless no-sandbox disable-gpu]
+    }
   )
+
+  Capybara::Selenium::Driver
+    .new(app, browser: :chrome, desired_capabilities: capabilities)
 end
 Capybara.default_max_wait_time = timeout

scripts/prepare_build.sh

 . scripts/utils.sh
+wget -q https://chromedriver.storage.googleapis.com/2.29/chromedriver_linux64.zip
+unzip chromedriver_linux64.zip -d /usr/local/bin
+
 export SETUP_DB=${SETUP_DB:-true}
 export USE_BUNDLE_INSTALL=${USE_BUNDLE_INSTALL:-true}
 export BUNDLE_INSTALL_FLAGS="--without production --jobs $(nproc) --path vendor --retry 3 --quiet"

spec/support/capybara.rb

 # rubocop:disable Style/GlobalVars
 require 'capybara/rails'
 require 'capybara/rspec'
-require 'capybara/poltergeist'
 require 'capybara-screenshot/rspec'
+require 'selenium-webdriver'
 # Give CI some extra time
 timeout = (ENV['CI'] || ENV['CI_SERVER']) ? 60 : 30
-Capybara.javascript_driver = :poltergeist
-Capybara.register_driver :poltergeist do |app|
-  Capybara::Poltergeist::Driver.new(
-    app,
-    js_errors: true,
-    timeout: timeout,
-    window_size: [1366, 768],
-    url_whitelist: %w[localhost 127.0.0.1],
-    url_blacklist: %w[.mp4 .png .gif .avi .bmp .jpg .jpeg],
-    phantomjs_options: [
-      '--load-images=yes'
-    ]
+Capybara.javascript_driver = :chrome
+Capybara.register_driver :chrome do |app|
+  capabilities = Selenium::WebDriver::Remote::Capabilities.chrome(
+    'chromeOptions' => {
+      'args' => %w[headless no-sandbox disable-gpu]
+    }
   )
+
+  Capybara::Selenium::Driver
+    .new(app, browser: :chrome, desired_capabilities: capabilities)
 end
 Capybara.default_max_wait_time = timeout