Support inline replay as described in the RFC  on lldb-dev. This extends the LLDB_RECORD macros to re-invoke the current function with arguments deserialized from the reproducer. This relies on the function being called in the exact same order as during replay. It uses the same mechanism to toggle the API boundary as during recording, which guarantees that only boundary crossing calls are replayed.
Another major change is that before this patch we could ignore the result of an API call, because we only cared about the observable behavior. Now we need to be able to return the replayed result to the SWIG bindings.
We reuse a lot of the recording infrastructure, which can be a little confusing at first. I'm open to renaming these things in a future patch, but I refrained from doing so here to make it easier to review.