Default APP_ABI for android_rpc application

Questions
1

app/src/main/jni/Application.mk

Personally, I think we should write APP_ABI ?= armeabi-v7a arm64-v8a ... instead of APP_ABI := armeabi-v7a arm64-v8a .... In the former case, APP_ABI will be overwritten by what we define in config.mk. Using the latter case, however, some runtime errors happen while the application is running on a armv7 processor.

2

This indeed is a better way, can you submit a PR ?

3

PR submitted.

Thanks for your reply~