check codepage for SJIS pathname test.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@13544 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

test/pathname/test_pathname.rb

@@ -174,8 +174,11 @@ class TestPathname < Test::Unit::TestCase
 
   if DOSISH
     defassert(:del_trailing_separator, "a", "a\\")
+    require 'Win32API'
+    if Win32API.new('kernel32', 'GetACP', nil, 'L').call == 932
       defassert(:del_trailing_separator, "\225\\", "\225\\\\") # SJIS
     end
+  end
 
   def plus(path1, path2) # -> path
     (Pathname.new(path1) + Pathname.new(path2)).to_s