* test/misc/test_ruby_mode.rb (assert_indent): since write-region
  in Emacs 25.1 no longer displays the "Wrote file" message, shows
  the explicit message to check if successfully finished.
  [ruby-core:77355] [Bug #12785]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@56224 b2dd03c8-39d4-4d8f-98ff-823fe69b080e