Clean up the implementation of the <dirent.h> functions.

Change-Id: I3c647cc9588525afc41fee90ee468d58cd13503a
diff --git a/tests/Android.mk b/tests/Android.mk
index e38aaf9..f948fea 100644
--- a/tests/Android.mk
+++ b/tests/Android.mk
@@ -25,6 +25,7 @@
     -Werror \
 
 test_src_files = \
+    dirent_test.cpp \
     getcwd_test.cpp \
     pthread_test.cpp \
     regex_test.cpp \