hidl_test: move duplicated code to shared lib

Test: hidl_test

Change-Id: Ia68b78d44d68a6b254c686afe64faf7cc89510d7
diff --git a/tests/foo/1.0/default/Android.bp b/tests/foo/1.0/default/Android.bp
index a2acd14..8571c87 100644
--- a/tests/foo/1.0/default/Android.bp
+++ b/tests/foo/1.0/default/Android.bp
@@ -13,6 +13,7 @@
     shared_libs: [
         "libbase",
         "libhidl",
+        "libfootest",
         "libhwbinder",
         "liblog",
         "libutils",