sb8x8 integration in rd loop.

Work-in-progress, not yet ready for review. TODO items:
- bitstream writing (encoder) and reading (decoder)
- decoder reconstruction

Change-Id: I5afb7284e7e0480847b47cd0097cb469433c9081

vp9/encoder/vp9_segmentation.c

@@ -199,9 +199,17 @@ static void count_segs_sb(VP9_COMP *cpi, MODE_INFO *mi,
     assert(bwl < bsl && bhl < bsl);
     if (bsize == BLOCK_SIZE_SB64X64) {
       subsize = BLOCK_SIZE_SB32X32;
+#if CONFIG_SB8X8
+    } else if (bsize == BLOCK_SIZE_SB32X32) {
+      subsize = BLOCK_SIZE_MB16X16;
+    } else {
+      assert(bsize == BLOCK_SIZE_MB16X16);
+      subsize = BLOCK_SIZE_SB8X8;
+#else
     } else {
       assert(bsize == BLOCK_SIZE_SB32X32);
       subsize = BLOCK_SIZE_MB16X16;
+#endif
     }
 
     for (n = 0; n < 4; n++) {