Add <stdio_ext.h> for elfutils.

Bug: 17139679
Change-Id: I1605ac382dbb6f23b2d874dbb9769f3cde4a6a99
diff --git a/tests/Android.mk b/tests/Android.mk
index b370b92..ef33afc 100644
--- a/tests/Android.mk
+++ b/tests/Android.mk
@@ -92,6 +92,7 @@
     stdatomic_test.cpp \
     stdint_test.cpp \
     stdio_test.cpp \
+    stdio_ext_test.cpp \
     stdlib_test.cpp \
     string_test.cpp \
     strings_test.cpp \