Take out reference_masking speed feature

This condition is not effectively in use. The actual reference
frame masking is done in other route.

Change-Id: Ia59c843bcac7243dada92f0f67658d7ce43df5e8

vp10/encoder/rdopt.c

diff --git a/vp10/encoder/rdopt.c b/vp10/encoder/rdopt.c
index 50da212..fd53bb6 100644
--- a/vp10/encoder/rdopt.c
+++ b/vp10/encoder/rdopt.c
@@ -2994,7 +2994,7 @@
       // are masked out.
       ref_frame_skip_mask[0] |= (1 << ref_frame);
       ref_frame_skip_mask[1] |= SECOND_REF_FRAME_MASK;
-    } else if (sf->reference_masking) {
+    } else {
       for (i = LAST_FRAME; i <= ALTREF_FRAME; ++i) {
         // Skip fixed mv modes for poor references
         if ((x->pred_mv_sad[ref_frame] >> 2) > x->pred_mv_sad[i]) {

vp10/encoder/speed_features.c

diff --git a/vp10/encoder/speed_features.c b/vp10/encoder/speed_features.c
index 5aeaf3b..d40383f 100644
--- a/vp10/encoder/speed_features.c
+++ b/vp10/encoder/speed_features.c
@@ -148,9 +148,6 @@
     sf->tx_size_search_method = frame_is_boosted(cpi) ? USE_FULL_RD
                                                       : USE_LARGESTALL;
 
-    // Reference masking is not supported in dynamic scaling mode.
-    sf->reference_masking = cpi->oxcf.resize_mode != RESIZE_DYNAMIC ? 1 : 0;
-
     sf->mode_search_skip_flags = (cm->frame_type == KEY_FRAME) ? 0 :
                                  FLAG_SKIP_INTRA_DIRMISMATCH |
                                  FLAG_SKIP_INTRA_BESTINTER |
@@ -279,13 +276,6 @@
                                  FLAG_SKIP_COMP_BESTINTRA |
                                  FLAG_SKIP_INTRA_LOWVAR;
     sf->adaptive_pred_interp_filter = 2;
-
-    // Disable reference masking if using spatial scaling since
-    // pred_mv_sad will not be set (since vp10_mv_pred will not
-    // be called).
-    // TODO(marpan/agrange): Fix this condition.
-    sf->reference_masking = (cpi->oxcf.resize_mode != RESIZE_DYNAMIC) ? 1 : 0;
-
     sf->disable_filter_search_var_thresh = 50;
     sf->comp_inter_joint_search_thresh = BLOCK_SIZES;
     sf->auto_min_max_partition_size = RELAXED_NEIGHBORING_MIN_MAX;
@@ -456,7 +446,6 @@
   sf->cb_partition_search = 0;
   sf->alt_ref_search_fp = 0;
   sf->use_quant_fp = 0;
-  sf->reference_masking = 0;
   sf->partition_search_type = SEARCH_PARTITION;
   sf->less_rectangular_check = 0;
   sf->use_square_partition_only = 0;

vp10/encoder/speed_features.h

diff --git a/vp10/encoder/speed_features.h b/vp10/encoder/speed_features.h
index cad0736..3969a2f 100644
--- a/vp10/encoder/speed_features.h
+++ b/vp10/encoder/speed_features.h
@@ -248,9 +248,6 @@
   // of the best so far.
   int mode_skip_start;
 
-  // TODO(JBB): Remove this.
-  int reference_masking;
-
   PARTITION_SEARCH_TYPE partition_search_type;
 
   // Used if partition_search_type = FIXED_SIZE_PARTITION