Merge branch 'rails5-silence-stream' into 'master'

Rails 5: replace removed silence_stream

See merge request gitlab-org/gitlab-ce!21387

changelogs/unreleased/rails5-silence-stream.yml

+---
+title: 'Rails 5: replace removed silence_stream'
+merge_request: 21387
+author: Jasper Maes
+type: other

lib/tasks/gettext.rake

@@ -82,7 +82,7 @@ namespace :gettext do
     # `gettext:find` writes touches to temp files to `stderr` which would cause
     # `static-analysis` to report failures. We can ignore these.
-    silence_stream($stderr) do
+    silence_sdterr do
       Rake::Task['gettext:find'].invoke
     end
@@ -118,4 +118,15 @@ namespace :gettext do
       end
     end
   end
+
+  def silence_sdterr(&block)
+    old_stderr = $stderr.dup
+    $stderr.reopen(File::NULL)
+    $stderr.sync = true
+
+    yield
+  ensure
+    $stderr.reopen(old_stderr)
+    old_stderr.close
+  end
 end