Change error.rs to use generated types.

This patch also removes AidlResult form the error module.
The new version of the Keystore 2.0 AIDL spec requires that ResponseCode
and ErrorCode will be returned as service specific error, instead of the
Result type.

Test: keystore2_test
Change-Id: I6f730b282c84abc8be2e693e5d2c7053648d7588
3 files changed