Turn errc and windows_error into enum classes.

llvm-svn: 209957
diff --git a/llvm/lib/Support/Windows/Path.inc b/llvm/lib/Support/Windows/Path.inc
index 8baa263..f04900c 100644
--- a/llvm/lib/Support/Windows/Path.inc
+++ b/llvm/lib/Support/Windows/Path.inc
@@ -810,7 +810,7 @@
     if (EC != windows_error::access_denied)
       return EC;
     if (is_directory(Name))
-      return error_code(errc::is_a_directory, posix_category());
+      return make_error_code(errc::is_a_directory);
     return EC;
   }
 
@@ -861,7 +861,7 @@
     if (EC != windows_error::access_denied)
       return EC;
     if (is_directory(Name))
-      return error_code(errc::is_a_directory, posix_category());
+      return make_error_code(errc::is_a_directory);
     return EC;
   }