fdtrack: add a test.

Test: logcat -c; fdtrack_test; logcat -d | grep fdtrack
Change-Id: Ie1101c9cf968299ec1f03f20097a2ed27f6e15bd
diff --git a/libfdtrack/Android.bp b/libfdtrack/Android.bp
index fd13512..a907d9a 100644
--- a/libfdtrack/Android.bp
+++ b/libfdtrack/Android.bp
@@ -16,3 +16,11 @@
     allow_undefined_symbols: true,
     recovery_available: true,
 }
+
+cc_test {
+    name: "fdtrack_test",
+    srcs: ["fdtrack_test.cpp"],
+    whole_static_libs: ["libBionicCtsGtestMain"],
+    static_libs: ["liblog"],
+    test_suites: ["device-tests"],
+}