DRILL-918: During Sort, handle the case where the child SelectionVector produces 0 records.
DRILL-799: Use static constants instead of Math.pow() to compute powers of 10 while adjusting scale of decimal data type.
DRILL-913: Fix IOOB in HashJoinProbe when input is empty batch
DRILL-924: Update trim so that it synchronized within the arena to avoid inconsistent state.
Run-time code generation support for reading Complex Type. WIP.

Use NullReader in generated code. More WIP.

Wrap singular value holder with a FieldReader.