Turn on adopted convolve precision rounding config

By default turn:
CONFIG_LOWPRECISION_BLEND=2
CONFIG_HIGHPRECISION_INTBUF=1

This is the adopted configuration from the codec WG.

Change-Id: Ic8a324a4bf6316753bea07a17160ab93afacca3b

build/cmake/aom_config_defaults.cmake

diff --git a/build/cmake/aom_config_defaults.cmake b/build/cmake/aom_config_defaults.cmake
index 3cacf06..284b2a7 100644
--- a/build/cmake/aom_config_defaults.cmake
+++ b/build/cmake/aom_config_defaults.cmake
@@ -120,7 +120,7 @@
 set(CONFIG_FRAME_SIZE 1 CACHE NUMBER "AV1 experiment flag.")
 set(CONFIG_FWD_KF 0 CACHE NUMBER "AV1 experiment flag.")
 set(CONFIG_HASH_ME 0 CACHE NUMBER "AV1 experiment flag.")
-set(CONFIG_HIGHPRECISION_INTBUF 0 CACHE NUMBER "AV1 experiment flag.")
+set(CONFIG_HIGHPRECISION_INTBUF 1 CACHE NUMBER "AV1 experiment flag.")
 set(CONFIG_HORZONLY_FRAME_SUPERRES 1 CACHE NUMBER "AV1 experiment flag.")
 set(CONFIG_INTER_STATS_ONLY 0 CACHE NUMBER "AV1 experiment flag.")
 set(CONFIG_INTRABC 1 CACHE NUMBER "AV1 experiment flag.")
@@ -130,7 +130,7 @@
 set(CONFIG_LOOPFILTERING_ACROSS_TILES_EXT 1 CACHE NUMBER "AV1 experiment flag.")
 set(CONFIG_LOOPFILTER_LEVEL 1 CACHE NUMBER "AV1 experiment flag.")
 set(CONFIG_LOOP_RESTORATION 1 CACHE NUMBER "AV1 experiment flag.")
-set(CONFIG_LOWPRECISION_BLEND 0 CACHE NUMBER "AV1 experiment flag.")
+set(CONFIG_LOWPRECISION_BLEND 2 CACHE NUMBER "AV1 experiment flag.")
 set(CONFIG_LV_MAP 1 CACHE NUMBER "AV1 experiment flag.")
 set(CONFIG_MAX_TILE 1 CACHE NUMBER "AV1 experiment flag.")
 set(CONFIG_MFMV 1 CACHE NUMBER "AV1 experiment flag.")

test/decode_to_md5.sh

diff --git a/test/decode_to_md5.sh b/test/decode_to_md5.sh
index b21570f..e02a3c8 100755
--- a/test/decode_to_md5.sh
+++ b/test/decode_to_md5.sh
@@ -57,7 +57,7 @@
 
 decode_to_md5_av1() {
   # expected MD5 sum for the last frame.
-  local expected_md5="85ccfd374240849e6849f917cf742c9e"
+  local expected_md5="155facd9ade570f14502bbfcaaeeca06"
   local file="${AV1_IVF_FILE}"
 
   # TODO(urvang): Check in the encoded file (like libvpx does) to avoid