Adding const to tree pointer inside vp9_extra_bit struct.

Change-Id: I60e02fa3de930ff1f969687ab5af93dee40d86ad

vp9/common/vp9_entropy.h

diff --git a/vp9/common/vp9_entropy.h b/vp9/common/vp9_entropy.h
index ccb9c4c..67b1669 100644
--- a/vp9/common/vp9_entropy.h
+++ b/vp9/common/vp9_entropy.h
@@ -51,7 +51,7 @@
 extern struct vp9_token vp9_coef_encodings[MAX_ENTROPY_TOKENS];
 
 typedef struct {
-  vp9_tree_index *tree;
+  const vp9_tree_index *tree;
   const vp9_prob *prob;
   int len;
   int base_val;

vp9/encoder/vp9_bitstream.c

diff --git a/vp9/encoder/vp9_bitstream.c b/vp9/encoder/vp9_bitstream.c
index e1978d4..1eda842 100644
--- a/vp9/encoder/vp9_bitstream.c
+++ b/vp9/encoder/vp9_bitstream.c
@@ -256,15 +256,15 @@
   }
 }
 
-static void pack_mb_tokens(vp9_writer* const bc,
+static void pack_mb_tokens(vp9_writer* const w,
                            TOKENEXTRA **tp,
                            const TOKENEXTRA *const stop) {
   TOKENEXTRA *p = *tp;
 
   while (p < stop && p->token != EOSB_TOKEN) {
     const int t = p->token;
-    const struct vp9_token *const a = vp9_coef_encodings + t;
-    const vp9_extra_bit *const b = vp9_extra_bits + t;
+    const struct vp9_token *const a = &vp9_coef_encodings[t];
+    const vp9_extra_bit *const b = &vp9_extra_bits[t];
     int i = 0;
     const vp9_prob *pp;
     int v = a->value;
@@ -287,7 +287,7 @@
 
     do {
       const int bb = (v >> --n) & 1;
-      vp9_write(bc, bb, pp[i >> 1]);
+      vp9_write(w, bb, pp[i >> 1]);
       i = vp9_coef_tree[i + bb];
     } while (n);
 
@@ -302,12 +302,12 @@
 
         do {
           const int bb = (v >> --n) & 1;
-          vp9_write(bc, bb, pb[i >> 1]);
+          vp9_write(w, bb, pb[i >> 1]);
           i = b->tree[i + bb];
         } while (n);
       }
 
-      vp9_write_bit(bc, e & 1);
+      vp9_write_bit(w, e & 1);
     }
     ++p;
   }

vp9/encoder/vp9_tokenize.c

diff --git a/vp9/encoder/vp9_tokenize.c b/vp9/encoder/vp9_tokenize.c
index 11dd0c0..3d21ea8 100644
--- a/vp9/encoder/vp9_tokenize.c
+++ b/vp9/encoder/vp9_tokenize.c
@@ -57,7 +57,7 @@
     // initialize the cost for extra bits for all possible coefficient value.
     {
       int cost = 0;
-      const vp9_extra_bit *p = vp9_extra_bits + t[i].token;
+      const vp9_extra_bit *p = &vp9_extra_bits[t[i].token];
 
       if (p->base_val) {
         const int extra = t[i].extra;
@@ -73,7 +73,7 @@
   } while (++i < DCT_MAX_VALUE);
 
   vp9_dct_value_tokens_ptr = dct_value_tokens + DCT_MAX_VALUE;
-  vp9_dct_value_cost_ptr   = dct_value_cost + DCT_MAX_VALUE;
+  vp9_dct_value_cost_ptr = dct_value_cost + DCT_MAX_VALUE;
 }
 
 struct tokenize_b_args {