Handle DT_UNKNOWN correctly during directory iteration.

Unlike stat and lstat, where unknown really means we know it's something weird,
during directory iteration DT_UNKNOWN simply means that the underlying FS doesn't
support the dirent::dt_type field.

This patch fixes libc++ to correctly set the cache to empty when DT_UNKNOWN is reported.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@337768 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed