Remove deprecated X connection test (UAT)

features/session/connection.feature

@@ -1,5 +0,0 @@
-Feature: connection to X server
-
-  Scenario: connects to X server
-    When I start uhwm
-    Then it must connect to X display

features/steps/x_steps.rb

@@ -36,11 +36,6 @@ When /^the window name changes to "([^"]+)"$/ do |name|
   x_client.window_name = name
 end
 
-Then /^it must connect to X display$/ do
-  uhwm_wait_ready
-  expect(x_socket_check uhwm.pid).to be true
-end
-
 Then /^the(?:\s(\w+))? window must be mapped$/ do |ident|
   timeout_until 'window not mapped after %d seconds' do
     x_window_map_state(x_client(ident).window_id) == 'IsViewable'

lib/uh/wm/testing/acceptance_helpers.rb

@@ -89,15 +89,6 @@ expected `#{message}' (#{times}) not seen after #{e.timeout} seconds in:
           fail "cannot simulate X key `#{k}'" unless system "xdotool key #{k}"
         end
 
-        def x_socket_check pid
-          case RbConfig::CONFIG['host_os']
-          when /linux/
-            `netstat -xp 2> /dev/null`.lines.grep /\s+#{pid}\/ruby/
-          else
-            `sockstat -u`.lines.grep /\s+ruby.+\s+#{pid}/
-          end.any?
-        end
-
         def x_window_map_state window_id
           `xwininfo -id #{window_id}`[/Map State: (\w+)/, 1]
         end