Old zxing issue:
https://code.google.com/p/zxing/issues/detail?id=1796
This is really strange, because GenericGF has a GenericGFPoly reference and
GenericGFPoly has a GenericGF reference the zxing:Ref "garbage collection" is
not working properly.
The bugfix replaced GenericGF zxing:Ref in GenericGFPoly with a normal reference.
The same trick is used at ModulusPoly.h (pdf417\decoder\ec).
is UPCA or EAN13. The old version returned an uninitialised Ref<Result>
(at the EAN13 case) which let MultiFormatUPCEANReader::decodeRow (line 90)
crash because a Result is assumed.
The bugfix is technically oriented at the java version.
Note: This error doesn't appear at normal tests because the MultiFormatUPCEANReader
uses the EAN13 reader for UPC-A detection. The UPCAReader is only used if
DecodeHints BarcodeFormat::UPC_A ist set.
