Fix missing dependency in contacts app tests.

Change-Id: I6895e81fffb22ab7ca5934a2db40238b1cc46ae5
diff --git a/tests/Android.mk b/tests/Android.mk
index 24c0685..1148966 100644
--- a/tests/Android.mk
+++ b/tests/Android.mk
@@ -18,6 +18,7 @@
 LOCAL_MIN_SDK_VERSION := 21
 
 LOCAL_STATIC_JAVA_LIBRARIES += \
+    android-support-test \
     hamcrest-library \
     mockito-target-minus-junit4