Fix assertion in bsls that will never fire with GCC.
Fix assertion in bsls that will never fire with GCC.

GCC will not warn or error when it encounters a zero-length array.
In order to make the assertions actually *assert* a negative array
length is used instead of zero.

saxena84/bde,che2/bde,che2/bde,idispatch/bde,saxena84/bde,che2/bde,bloomberg/bde,dbremner/bde,bloomberg/bde,minhlongdo/bde,mversche/bde,dbremner/bde,apaprocki/bde,minhlongdo/bde,osubboo/bde,frutiger/bde,frutiger/bde,bowlofstew/bde,frutiger/bde,osubboo/bde,bowlofstew/bde,osubboo/bde,jmptrader/bde,dbremner/bde,mversche/bde,jmptrader/bde,minhlongdo/bde,dbremner/bde,mversche/bde,dharesign/bde,idispatch/bde,apaprocki/bde,bloomberg/bde,idispatch/bde,osubboo/bde,saxena84/bde,apaprocki/bde,apaprocki/bde,apaprocki/bde,bowlofstew/bde,bloomberg/bde,mversche/bde,jmptrader/bde,frutiger/bde,bloomberg/bde,jmptrader/bde,dharesign/bde,bowlofstew/bde,dharesign/bde,saxena84/bde,che2/bde,dharesign/bde,idispatch/bde,minhlongdo/bde