Extract out test utility functions from resampler_tests

These will be used for mixer tests later.

Change-Id: I22b1c89857058cfb2450afe15e80d6c9306a31f1
diff --git a/services/audioflinger/tests/Android.mk b/services/audioflinger/tests/Android.mk
index 874f18f..f365637 100644
--- a/services/audioflinger/tests/Android.mk
+++ b/services/audioflinger/tests/Android.mk
@@ -1,5 +1,8 @@
 # Build the unit tests for audioflinger
 
+#
+# resampler unit test
+#
 LOCAL_PATH:= $(call my-dir)
 include $(CLEAR_VARS)
 
@@ -20,6 +23,7 @@
 	bionic/libstdc++/include \
 	external/gtest/include \
 	external/stlport/stlport \
+	$(call include-path-for, audio-utils) \
 	frameworks/av/services/audioflinger
 
 LOCAL_SRC_FILES := \