Turn on adaptive pred filter scheme for sub8x8 below 720p

For sequences of resolution below 720p, the encoder will check
intra prediction modes and inter prediction modes from LAST_FRAME.
This commit turns on adaptive prediction filter scheme for sub8x8
blocks, where inter prediction modes are enabled. For the test
sequence bus at CIF, the speed 2 runtime goes down from 17879 ms
to 16783 ms, i.e., 6% speed up. The compression performance of
derf set is down by -0.128%.

Change-Id: I01d5321a5ceab4e0666ac5be56c52d896c7a8d45

vp9/encoder/vp9_speed_features.c

@@ -88,13 +88,13 @@ static void set_good_speed_feature(VP9_COMP *cpi, VP9_COMMON *cm,
       sf->last_partitioning_redo_frequency = 3;
       sf->disable_split_mask = cm->show_frame ? DISABLE_ALL_SPLIT
                                               : DISABLE_ALL_INTER_SPLIT;
+      sf->adaptive_pred_interp_filter = 0;
     } else {
       sf->disable_split_mask = LAST_AND_INTRA_SPLIT_ONLY;
       sf->last_partitioning_redo_frequency = 2;
       sf->lf_motion_threshold = NO_MOTION_THRESHOLD;
     }
 
-    sf->adaptive_pred_interp_filter = 0;
     sf->reference_masking = 1;
     sf->mode_search_skip_flags = FLAG_SKIP_INTRA_DIRMISMATCH |
                                  FLAG_SKIP_INTRA_BESTINTER |
@@ -115,6 +115,8 @@ static void set_good_speed_feature(VP9_COMP *cpi, VP9_COMMON *cm,
     else
       sf->disable_split_mask = DISABLE_ALL_INTER_SPLIT;
 
+    sf->adaptive_pred_interp_filter = 0;
+
     sf->lf_motion_threshold = LOW_MOTION_THRESHOLD;
     sf->last_partitioning_redo_frequency = 3;
     sf->recode_loop = ALLOW_RECODE_KFMAXBW;