Force all zero txfm in skip_txfm mode

Change-Id: I19793c397263da01bd24f0717bfa2c393d6503fd

av1/encoder/encodemb.c

diff --git a/av1/encoder/encodemb.c b/av1/encoder/encodemb.c
index f54ebc1..4707ccf 100644
--- a/av1/encoder/encodemb.c
+++ b/av1/encoder/encodemb.c
@@ -746,8 +746,12 @@
 
   TX_TYPE tx_type = DCT_DCT;
   const int bw = mi_size_wide[plane_bsize];
-  if (plane == 0 && is_blk_skip(x->txfm_search_info.blk_skip, plane,
-                                blk_row * bw + blk_col)) {
+
+  if (xd->mi[0]->skip_txfm) {
+    *eob = 0;
+    p->txb_entropy_ctx[block] = 0;
+  } else if (plane == 0 && is_blk_skip(x->txfm_search_info.blk_skip, plane,
+                                       blk_row * bw + blk_col)) {
     *eob = 0;
     p->txb_entropy_ctx[block] = 0;
   } else {