libvpx: Pull from upstream

source/libvpx/vp9/decoder/vp9_treereader.h

 /*
  *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
 
 #ifndef VP9_DECODER_VP9_TREEREADER_H_
 #define VP9_DECODER_VP9_TREEREADER_H_
 
 #include "vp9/common/vp9_treecoder.h"
 #include "vp9/decoder/vp9_dboolhuff.h"
 
-#define vp9_read_prob(r) ((vp9_prob)vp9_read_literal(r, 8))
 #define vp9_read_and_apply_sign(r, value) (vp9_read_bit(r) ? -(value) : (value))
 
 // Intent of tree data structure is to make decoding trivial.
 static int treed_read(vp9_reader *const r, /* !!! must return a 0 or 1 !!! */
                       vp9_tree t,
                       const vp9_prob *const p) {
   register vp9_tree_index i = 0;
 
   while ((i = t[ i + vp9_read(r, p[i >> 1])]) > 0);
 
   return -i;
 }
 
 #endif  // VP9_DECODER_VP9_TREEREADER_H_