The difference between this and regular LLDB_LOG is that this one clears
the error object unconditionally. This was inspired by the
ObjectFileELF bug (r322664), where the error object was being cleared
only if logging was enabled.
Of course, one could argue that since our logging is optional, it does
not really qualify as "handling" the error and we should leave it up to
the programmer to explicitly clear it if he really wants to.
It's not really clear to me which position is better. What do you think?