Fix listing of '' and '/'.

runtime/bin/directory_android.cc

Index: runtime/bin/directory_android.cc
diff --git a/runtime/bin/directory_android.cc b/runtime/bin/directory_android.cc
index 02f841deb3321318fc8ad505a82cb2bec7f94149..e89dd058bea9a20daee461b01b0c1b0d7ec0d264 100644
--- a/runtime/bin/directory_android.cc
+++ b/runtime/bin/directory_android.cc
@@ -79,11 +79,6 @@ ListType DirectoryListingEntry::Next(DirectoryListing* listing) {
   }
 
   if (lister_ == 0) {
-    if (!listing->path_buffer().Add(File::PathSeparator())) {
-      done_ = true;
-      return kListError;
-    }
-    path_length_ = listing->path_buffer().length();
     do {
       lister_ = reinterpret_cast<intptr_t>(
           opendir(listing->path_buffer().AsString()));
@@ -93,6 +88,12 @@ ListType DirectoryListingEntry::Next(DirectoryListing* listing) {
       done_ = true;
       return kListError;
     }
+    if (parent_ != NULL) {
+      if (!listing->path_buffer().Add(File::PathSeparator())) {
+        return kListError;
+      }
+    }
+    path_length_ = listing->path_buffer().length();
   }
   // Reset.
   listing->path_buffer().Reset(path_length_);