presto-spi/src/main/java/io/prestosql/spi/block/VariableWidthBlockBuilder.java/VariableWidthBlockBuilder/updateArraysDataSize
class VariableWidthBlockBuilder:    private void updateArraysDataSize()
    {
        arraysRetainedSizeInBytes = sizeOf(valueIsNull) + sizeOf(offsets);
    }