EOFException on NCDump data

[Mikhail-Aoun]

Hi,
As explained in Unidata/thredds#1342, we've found an issue when trying to read data from some particular netcdf files.
The same bug happens with Tools UI latest stable release (Version 5.3.3) and the same netcdf files as the one attached in the other issue. This time, we met an EOFException in the ucar.nc2.internal.iosp.hdf5.H5objects$GlobalHeap instantiation algorithm.

The Tools UI Exception when you open this file and try to NCDump tm_packets data is :

ubyte tm_packets(number_tm_packets=10256, *);
:long_name = "Array of TM packets";

data:
java.io.EOFException
at ucar.unidata.io.RandomAccessFile.readInt(RandomAccessFile.java:1233)
at ucar.unidata.io.RandomAccessFile.readLong(RandomAccessFile.java:1319)
at ucar.nc2.internal.iosp.hdf5.H5headerNew.readLength(H5headerNew.java:2215)
at ucar.nc2.internal.iosp.hdf5.H5objects$GlobalHeap.(H5objects.java:2631)
at ucar.nc2.internal.iosp.hdf5.H5objects$HeapIdentifier.getHeapObject(H5objects.java:2544)
at ucar.nc2.internal.iosp.hdf5.H5headerNew.getHeapDataArray(H5headerNew.java:2055)
at ucar.nc2.internal.iosp.hdf5.H5headerNew.getHeapDataArray(H5headerNew.java:2048)
at ucar.nc2.internal.iosp.hdf5.H5iospNew.readData(H5iospNew.java:338)
at ucar.nc2.internal.iosp.hdf5.H5iospNew.readData(H5iospNew.java:255)
at ucar.nc2.internal.iosp.hdf5.H5iospNew.readData(H5iospNew.java:191)
at ucar.nc2.NetcdfFile.readData(NetcdfFile.java:2110)
at ucar.nc2.Variable.reallyRead(Variable.java:761)
at ucar.nc2.Variable._read(Variable.java:731)
at ucar.nc2.Variable._read(Variable.java:773)
at ucar.nc2.Variable.read(Variable.java:597)
at ucar.nc2.NetcdfFile.readSection(NetcdfFile.java:2139)
at ucar.nc2.ui.op.NCdumpPane$NCdumpTask.run(NCdumpPane.java:330)
at java.lang.Thread.run(Unknown Source)

Analysis and correction :
As with the Unidata/thredds#1342 issue, the bug seems to be linked to the ucar.nc2.internal.iosp.hdf5.H5objects$GlobalHeap instantiation algorithm which doesn't handle correctly some particular file byte structures.
We've managed to find a similar fix which work with ToolsUI. I will submit the associated Pull request.