libvpx: Pull from upstream

source/libvpx/vp9/common/vp9_pred_common.c

Index: source/libvpx/vp9/common/vp9_pred_common.c
diff --git a/source/libvpx/vp9/common/vp9_pred_common.c b/source/libvpx/vp9/common/vp9_pred_common.c
index fd735f48361dfa4ae2531a64f1ac4c148d0584ce..0aac4a9e677bb5fe5023fefeec301d9c5df79917 100644
--- a/source/libvpx/vp9/common/vp9_pred_common.c
+++ b/source/libvpx/vp9/common/vp9_pred_common.c
@@ -344,7 +344,7 @@ int vp9_get_pred_context_single_ref_p2(const MACROBLOCKD *xd) {
 // left of the entries corresponding to real blocks.
 // The prediction flags in these dummy entries are initialized to 0.
 int vp9_get_tx_size_context(const MACROBLOCKD *xd) {
-  const int max_tx_size = max_txsize_lookup[xd->mi[0].src_mi->mbmi.sb_type];
+  const int max_tx_size = max_txsize_lookup[xd->mi[0]->mbmi.sb_type];
   const MB_MODE_INFO *const above_mbmi = xd->above_mbmi;
   const MB_MODE_INFO *const left_mbmi = xd->left_mbmi;
   const int has_above = xd->up_available;