This is a debug tool used to detect bitstream error. On encoder side, it pushes
each bit and probability into a queue before the bit is written into the
Arithmetic coder. On decoder side, whenever a bit is read out from the
Arithmetic coder, it pops up the reference bit and probability from the queue as
well. If the two results do not match, this debug tool will report an error.
This tool can be used to pin down the bitstream error precisely. By combining
gdb's backtrace method, we can detect which module causes the bitstream error.

Change-Id: I133a4371fafdd48c488f2ca47f9e395676c401f2