Remove CONFIG_CB4X4 config options

Change-Id: I6902e642021a8473f1603d7751c63edca702b199
diff --git a/build/cmake/aom_config_defaults.cmake b/build/cmake/aom_config_defaults.cmake
index a037a01..8963efc 100644
--- a/build/cmake/aom_config_defaults.cmake
+++ b/build/cmake/aom_config_defaults.cmake
@@ -110,7 +110,6 @@
 set(CONFIG_ANS 0 CACHE NUMBER "AV1 experiment flag.")
 set(CONFIG_AOM_QM 1 CACHE NUMBER "AV1 experiment flag.")
 set(CONFIG_BGSPRITE 0 CACHE NUMBER "AV1 experiment flag.")
-set(CONFIG_CB4X4 1 CACHE NUMBER "AV1 experiment flag.")
 set(CONFIG_CDEF 1 CACHE NUMBER "AV1 experiment flag.")
 set(CONFIG_CDEF_SINGLEPASS 0 CACHE NUMBER "AV1 experiment flag.")
 set(CONFIG_CFL 0 CACHE NUMBER "AV1 experiment flag.")
diff --git a/build/cmake/aom_configure.cmake b/build/cmake/aom_configure.cmake
index 03f596e..890234b 100644
--- a/build/cmake/aom_configure.cmake
+++ b/build/cmake/aom_configure.cmake
@@ -56,10 +56,9 @@
     unset(var_helpstring)
     get_property(var_helpstring CACHE ${var} PROPERTY HELPSTRING)
     if ("${var_helpstring}" STREQUAL "AV1 experiment flag.")
-      if ("${var}" MATCHES "CONFIG_CB4X4\|CONFIG_TXMG")
-       # CB4X4 is required and can not be disabled.
+      if ("${var}" MATCHES "CONFIG_TXMG")
        # TXMG is required for configure compatibility.
-     else ()
+      else ()
        set(${var} 0)
      endif ()
     endif ()
diff --git a/configure b/configure
index 52a92e2..046d122 100755
--- a/configure
+++ b/configure
@@ -292,7 +292,6 @@
     daala_tx16
     daala_tx32
     daala_tx64
-    cb4x4
     chroma_sub8x8
     frame_size
     ext_delta_q
@@ -502,8 +501,6 @@
         enabled ${c} && enable_feature ${c##*_}s
     done
 
-    enable_feature cb4x4
-
     # Enable adopted experiments by default
     soft_enable adopted_experiments
     if enabled adopted_experiments; then
@@ -560,7 +557,6 @@
     enabled ctx1d && soft_enable ext_tx
     enabled compound_round && soft_enable convolve_round
     enabled intra_edge && enable_feature ext_intra
-    enabled chroma_sub8x8 && enable_feature cb4x4
     enabled ncobmc_adapt_weight && enable_feature motion_var
     enabled bgsprite && enable_feature global_motion
     enabled ext_comp_refs && enable_feature one_sided_compound