Enable palette-delta-encoding by default

Change-Id: I9000dfbcc35ac85d7008513ede5163c59349d912

build/cmake/aom_config_defaults.cmake

diff --git a/build/cmake/aom_config_defaults.cmake b/build/cmake/aom_config_defaults.cmake
index 8374c35..4f887a0 100644
--- a/build/cmake/aom_config_defaults.cmake
+++ b/build/cmake/aom_config_defaults.cmake
@@ -174,7 +174,7 @@
 set(CONFIG_NO_FRAME_CONTEXT_SIGNALING 0 CACHE NUMBER "AV1 experiment flag.")
 set(CONFIG_OBU 0 CACHE NUMBER "AV1 experiment flag.")
 set(CONFIG_OPT_REF_MV 0 CACHE NUMBER "AV1 experiment flag.")
-set(CONFIG_PALETTE_DELTA_ENCODING 0 CACHE NUMBER "AV1 experiment flag.")
+set(CONFIG_PALETTE_DELTA_ENCODING 1 CACHE NUMBER "AV1 experiment flag.")
 set(CONFIG_PALETTE_THROUGHPUT 1 CACHE NUMBER "AV1 experiment flag.")
 set(CONFIG_PARALLEL_DEBLOCKING 1 CACHE NUMBER "AV1 experiment flag.")
 set(CONFIG_Q_ADAPT_PROBS 0 CACHE NUMBER "AV1 experiment flag.")

configure

diff --git a/configure b/configure
index 685b6b0..ec1b0fb 100755
--- a/configure
+++ b/configure
@@ -526,6 +526,7 @@
       soft_enable kf_ctx
       soft_enable striped_loop_restoration
       soft_enable ext_intra_mod
+      soft_enable palette_delta_encoding
     fi
 
     # Enable low-bitdepth pixel pipeline by default