PARQUET-152: Add validation on Encoding.DELTA_BYTE_ARRAY to allow FIX…

[spena]

PARQUET-152: Add validation on Encoding.DELTA_BYTE_ARRAY to allow FIXED_LEN_BYTE_ARRAY types.

• FIXED_LEN_BYTE_ARRAY types are binary values that may use DELTA_BYTE_ARRAY encoding,
  so they should be allowed to be decoded using the same DELTA_BYTE_ARRAY encoding.

@rdblue @nezihyigitbasi Could you review this fix?

I executed a test by writing a file that fall backs to DELTA_BYTE_ARRAY encoding, then read the file, and compare the read values with the written values, and it worked fine.

[nezihyigitbasi]

@spena this problem was previously causing failures during read benchmarks, I verified that this change at least makes the benchmarks go through.
@rdblue are there any other types that can use the DELTA_BYTE_ARRAY encoding?

[spena]

ParquetProperties.writerToFallbackTo() shows that only BINARY and FIXED_LEN_BYTE_ARRAY are supported for DELTA_BYTE_ARRAY:

...
case BOOLEAN:
        return new RunLengthBitPackingHybridValuesWriter(1, initialSizePerCol, pageSize);
case BINARY:
case FIXED_LEN_BYTE_ARRAY:
        return new DeltaByteArrayWriter(initialSizePerCol, pageSize);
case INT32:
...

[rdblue]

Looks good to me. I don't think anything else should use DELTA_BYTE_ARRAY.