Build 'libminijail_test' as BUILD_NATIVE_TEST.

Bug: 36219649
Test: mmma external/minijail, adb sync, run test on device.
Change-Id: Ife8942c2f2937a156e10631a127d6e415cf11c8e
diff --git a/Android.mk b/Android.mk
index 320f48a..b45d975 100644
--- a/Android.mk
+++ b/Android.mk
@@ -225,11 +225,12 @@
 
 LOCAL_CFLAGS := $(minijailCommonCFlags)
 LOCAL_CLANG := true
+LOCAL_GTEST := false
 LOCAL_SRC_FILES := \
 	test/libminijail_test.cpp
 
 LOCAL_SHARED_LIBRARIES := libbase libminijail
-include $(BUILD_EXECUTABLE)
+include $(BUILD_NATIVE_TEST)
 
 
 # libminijail usage example.