Add support for leaf arrays of UInt_t size (two.y[ny] in basic.cxx unit test).
Add support for leaf arrays of UInt_t size (two.y[ny] in basic.cxx unit test).

zzxuanyuan/root-compressor-dummy,zzxuanyuan/root-compressor-dummy,zzxuanyuan/root-compressor-dummy,zzxuanyuan/root-compressor-dummy,zzxuanyuan/root-compressor-dummy,zzxuanyuan/root-compressor-dummy,zzxuanyuan/root-compressor-dummy,zzxuanyuan/root-compressor-dummy,zzxuanyuan/root-compressor-dummy,zzxuanyuan/root-compressor-dummy,zzxuanyuan/root-compressor-dummy