[EXI] CH Event processing

Hi

       During encoding when we encounter a CH EVENT and if the current
grammar does not have a production with event code of length 1 matching CH
event we add a new production for CH with event code 0. This is quite
useful.

       But why should not the existing CH production be removed from the
grammar. I feel it is simply a place holder and in some cases can lead to
extra bit for encoding than necessary(when there are 2**n productions).

       So I suggest to remove the existing CH production when we are adding
a new CH production with event code length of 0. 

 

Regards

Santhanakrishnan