uint8_t segment and skip to avoid signed / unsigned warnings

Change-Id: I2e2765b851fb0a1b15351c2aa0e079197cbee373

vp9/common/vp9_blockd.h

@@ -124,9 +124,9 @@ typedef struct {
   BLOCK_SIZE sb_type;
   PREDICTION_MODE mode;
   TX_SIZE tx_size;
-  uint8_t skip;
-  uint8_t segment_id;
-  uint8_t seg_id_predicted;  // valid only when temporal_update is enabled
+  int8_t skip;
+  int8_t segment_id;
+  int8_t seg_id_predicted;  // valid only when temporal_update is enabled
 
   // Only for INTRA blocks
   PREDICTION_MODE uv_mode;

vp9/encoder/vp9_encodemb.c

@@ -32,7 +32,7 @@ struct optimize_ctx {
 struct encode_b_args {
   MACROBLOCK *x;
   struct optimize_ctx *ctx;
-  unsigned char *skip;
+  int8_t *skip;
 };
 
 void vp9_subtract_block_c(int rows, int cols,
@@ -699,7 +699,7 @@ static void encode_block_intra(int plane, int block, BLOCK_SIZE plane_bsize,
 
 void vp9_encode_block_intra(MACROBLOCK *x, int plane, int block,
                             BLOCK_SIZE plane_bsize, TX_SIZE tx_size,
-                            unsigned char *skip) {
+                            int8_t *skip) {
   struct encode_b_args arg = {x, NULL, skip};
   encode_block_intra(plane, block, plane_bsize, tx_size, &arg);
 }

vp9/encoder/vp9_encodemb.h

@@ -33,7 +33,7 @@ void vp9_subtract_plane(MACROBLOCK *x, BLOCK_SIZE bsize, int plane);
 
 void vp9_encode_block_intra(MACROBLOCK *x, int plane, int block,
                             BLOCK_SIZE plane_bsize, TX_SIZE tx_size,
-                            unsigned char *skip);
+                            int8_t *skip);
 
 void vp9_encode_intra_block_plane(MACROBLOCK *x, BLOCK_SIZE bsize, int plane);