This as added to make while-loops easy:
while iter.next() {
...
}
But this involves adding a layer of custom logic on top of the RocksDB
API. This is probably a bad idea given that this API is meant to closely
match the underlying iterator API in RocksDB, so this commit changes
that.
The new way to iterate is as follows:
while iter.valid() {
...
iter.next();
}