Apply some small refactors after code review

app/helpers/license_helper.rb

@@ -60,9 +60,10 @@ module LicenseHelper
   end
 
   def new_trial_url
+    return_to_url = URI.encode(Gitlab.config.gitlab.url)
     uri = URI.parse(Gitlab::SUBSCRIPTIONS_URL)
     uri.path = '/trials/new'
-    uri.query = "return_to=#{Gitlab.config.gitlab.url}"
+    uri.query = "return_to=#{return_to_url}"
     uri.to_s
   end
 

app/models/license.rb

@@ -201,10 +201,6 @@ class License < ActiveRecord::Base
       return unless license && license.valid?
       license
     end
-
-    def trial
-      all.detect { |license| license.trial? }
-    end
   end
 
   def data_filename

app/views/dashboard/projects/_zero_authorized_projects.html.haml

 - admin_without_ee_license = !current_license && current_user.admin?
 
-.row.blank-state-parent-container{ class: "#{ 'has-start-trial-container' if admin_without_ee_license }" }
+.row.blank-state-parent-container{ class: ('has-start-trial-container' if admin_without_ee_license) }
   .section-container.section-welcome{ class: "#{ 'col-md-6' if admin_without_ee_license }" }
     .container.section-body
       .blank-state.blank-state-welcome

app/views/layouts/_page.html.haml

-.page-with-sidebar.js-page-with-sidebar{ class: "#{('page-with-new-sidebar' if defined?(@new_sidebar) && @new_sidebar)} #{page_gutter_class}" }
+.page-with-sidebar.js-page-with-sidebar{ class: [('page-with-new-sidebar' if @new_sidebar), page_gutter_class] }
   - if show_new_nav?
     - if defined?(nav) && nav
       = render "layouts/nav/#{nav}"

app/views/layouts/header/_ee_trial_banner.html.haml

 - if current_license&.trial? && license_message.present?
-  .alert.alert-dismissible.gitlab-ee-trial-banner.hidden.js-gitlab-ee-trial-banner{ role: 'alert', 'data-license-expiry' => current_license.expires_at }
+  .alert.alert-dismissible.gitlab-ee-trial-banner.hidden.js-gitlab-ee-trial-banner{ role: 'alert', data: { license_expiry: current_license.expires_at }}
     %button.close{ type: 'button', 'data-dismiss' => 'alert', 'aria-label' => 'Dismiss banner' }
       = icon('times', 'aria-hidden' => 'true')
     %p