Copy reactor classes to new directory

Test: compile and run unit test
Change-Id: Ie704bf6b80f24bcae86d557ca351a893dcf8bdfa
diff --git a/Android.bp b/Android.bp
index 469d7fb..49af99c 100644
--- a/Android.bp
+++ b/Android.bp
@@ -8,6 +8,7 @@
     "audio_bluetooth_hw",
     "audio_hal_interface",
     "audio_hearing_aid_hw",
+    "gd",
     "hci",
     "utils",
     "device",