Unexpected behavior of the CurrentBatchRowCount() method

In version 2.0.8 of the library, this method always returns 0, even though the dataset contains records. In earlier versions of the library, the RowCount property worked correctly and returned the actual number of records.

Code example:

```csharp
var count = dataset.CurrentBatchRowCount();
// variable count always contains 0

var list = new List(count);
while (await dataset.HasNextAsync())
{
var row = dataset.Next();
list.Add(new DataItem(row, false));
}
```

Start by reproducing the issue with the provided C# example against library version 2.0.8, then inspect the implementation of CurrentBatchRowCount() and compare it with the earlier RowCount behavior. Done means the method returns the dataset's actual record count and the example no longer initializes the list with zero.

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