NoData/NullCellValue not being written to ERS

[lpinner]

NoData values don't get written to ERS header files, for example:

>gdalinfo --version
GDAL 1.8.1, released 2011/07/09
>gdal_translate -of ers -a_nodata 0 test.tif test.ers

I would expect test.ers to contain a 'NullCellValue = 0' entry, but it does not.

Test files attached.

[lpinner]

Test files

[Even Rouault]

r22997 /trunk/ (autotest/gdrivers/ers.py gdal/frmts/ers/ersdataset.cpp): ERS: implement ERSRasterBand::SetNoDataValue() (#4207)