MemoryStream Set: incorrect get size and write to buffer causes exception (C# generator)

E.g. we have input stream with Length = 100 and Capacity = 1000.

```
public override void Set(MemoryStream value)
...
uint fbeBytesSize = (uint)value.Length; // here we have 100
...
Write(fbeBytesOffset + 4, value.GetBuffer()); // and trying to write 1000
```

Proposed solution (to c# generator)?
```
 Write(fbeBytesOffset + 4, value.GetBuffer(), 0, fbeBytesSize);
```