This reverts commit dc2da0edc5.
Add pb_close_string_substream() for copying back the state.
This makes adding error messages easier in the future, as also
them need to be propagated back from the substream.
This reverts commit dc2da0edc5.
Add pb_close_string_substream() for copying back the state.
This makes adding error messages easier in the future, as also
them need to be propagated back from the substream.