Android 10 multi screen input method(multi-client input editor)

original IME is not compatible with multi-client input editor

AOSP 10 has an multi-client IME sample under development/samples/MultiClientInputMethod

1. make -j MultiClientInputMethod
2. $ adb install -r $OUT/system/priv-app/MultiClientInputMethod/MultiClientInputMethod.apk
3. $ adb root
4. $ adb shell setprop persist.debug.multi_client_ime \
com.example.android.multiclientinputmethod/.MultiClientInputMethod
5. $ adb reboot