771444a8ac
Introduce "aidl4" variant of service manager to adapt the change
to service related protocol for Android 12.
From Android 12, when reading nullable strong binder, the format of
the `stability` field passed on the wire was changed and evolved to
`struct Category`, which consists of the following members with 4 bytes long.
```
struct Category {
uint8_t version;
uint8_t reserved[2];
Level level; <- bitmask of Stability::Level
}
```
Please check the following link for details:
https://cs.android.com/android/platform/superproject/+/android-12.0.0_r3:frameworks/native/libs/binder/include/binder/Stability.h;l=140
To honor the change on AOSP side for Android 12, we need to adapt
the protocol change in Service Manager.