Support overwriting an arbitrary number of literal bits.
Support overwriting an arbitrary number of literal bits.

Overwriting was only guaranteed to work if a whole number
of bytes were being overwritten.

Change-Id: I5e72cb337ec6ff691e93288de9f751b583654a17

mbebenita/aom,luctrudeau/aom,mbebenita/aom,smarter/aom,mbebenita/aom,smarter/aom,mbebenita/aom,mbebenita/aom,GrokImageCompression/aom,mbebenita/aom,luctrudeau/aom,mbebenita/aom,GrokImageCompression/aom,luctrudeau/aom,GrokImageCompression/aom,mbebenita/aom,GrokImageCompression/aom,luctrudeau/aom,smarter/aom,luctrudeau/aom,luctrudeau/aom,smarter/aom,GrokImageCompression/aom,smarter/aom,mbebenita/aom,GrokImageCompression/aom,smarter/aom