directory. Current directory is not the top source directory when
  the building process runs on other than there.

* test/rake/test_rake_rake_test_loader.rb: ditto.

* test/rake/test_rake_task_argument_parsing.rb
  (test_terminal_width_using_hardcoded_80): hardcoded 80 is used
  when app.unix? is false.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@32642 b2dd03c8-39d4-4d8f-98ff-823fe69b080e