register_type returns error when it fails

1. execute register_type only if check_api is turned off
2. when register_type fails(GetReturnType returns nullptr, etc..), it
returns false, and then load_and_validate_aidl returns
AidlError::BAD_TYPE

Bug: 110967839

Test: m -j
Test: ./runtests.sh

Change-Id: I547f6b96163924d4dc66e56d6e5e6ff1204cd9db
1 file changed