Enable kf-ctx by default

Adopted by AOM WG on 08/17.

Change-Id: I3e5b369e9d8220c7b3f9e6f9d300eb640e2bf3a8

build/cmake/aom_config_defaults.cmake

diff --git a/build/cmake/aom_config_defaults.cmake b/build/cmake/aom_config_defaults.cmake
index a584f56..51c0421 100644
--- a/build/cmake/aom_config_defaults.cmake
+++ b/build/cmake/aom_config_defaults.cmake
@@ -156,7 +156,7 @@
 set(CONFIG_INTRABC 0 CACHE NUMBER "AV1 experiment flag.")
 set(CONFIG_INTRA_EDGE 1 CACHE NUMBER "AV1 experiment flag.")
 set(CONFIG_JNT_COMP 0 CACHE NUMBER "AV1 experiment flag.")
-set(CONFIG_KF_CTX 0 CACHE NUMBER "AV1 experiment flag.")
+set(CONFIG_KF_CTX 1 CACHE NUMBER "AV1 experiment flag.")
 set(CONFIG_LGT 0 CACHE NUMBER "AV1 experiment flag.")
 set(CONFIG_LGT_FROM_PRED 0 CACHE NUMBER "AV1 experiment flag.")
 set(CONFIG_LOOPFILTERING_ACROSS_TILES 1 CACHE NUMBER "AV1 experiment flag.")

configure

diff --git a/configure b/configure
index 703e68d..e928d4c 100755
--- a/configure
+++ b/configure
@@ -532,6 +532,7 @@
       soft_enable cfl
       soft_enable deblock_13tap
       soft_enable frame_marker
+      soft_enable kf_ctx
     fi
 
     # Enable low-bitdepth pixel pipeline by default