platform build with app including gradle.

Gradle을 포함한 app 빌드를 위한 Android.mk 에제

#app/build.gradle
LOCAL_PATH := $(call my-dir)
TEST_JNI_TOP := $(LOCAL_PATH)

$(info $(shell cd $(TEST_JNI_TOP) &&./gradlew assembleRelease))

include $(CLEAR_VARS)
LOCAL_MODULE :=TestJNI
LOCAL_MODULE_CLASS := APPS
#LOCAL_SRC_FILES := app/build/outputs/apk/release/app-release-unsigned.apk
LOCAL_SRC_FILES := app/build/outputs/apk/release/TestJNI.apk
LOCAL_CERTIFICATE := platform
LOCAL_PRIVILEGED_MODULE := true
include $(BUILD_PREBUILT)

#local.properties
sdk.dir=/opt/android-sdk-linux/
ndk.dir=/opt/android-ndk-r15c/

LOCAL_PRIVILEGED_MODULE true 때문에 apk는 아래의 경로에 생성 된다.

[100% 1/1] Install: out/target/product/~~/system/priv-app/TestJNI/TestJNI.apk