Speed 2 alternative balance.

A previous path improved speed 2 quality a little but
more extensive testing showed that it slowed encode
by a few %.

The change will have a similar effect for speed 3 but
should not impact speeds 4+;

This experiment should reverse that and give a speed
up at the cost of a small quality loss.

Borg results pending.

Change-Id: I4493fc1541aaf44587f1a41ff219f7088da9252c

vp9/encoder/vp9_speed_features.c

@@ -73,8 +73,8 @@ static void set_good_speed_feature(VP9_COMP *cpi, VP9_COMMON *cm,
   }
 
   if (speed >= 2) {
-    sf->tx_size_search_method = vp9_frame_is_boosted(cpi) ? USE_FULL_RD
-                                                          : USE_LARGESTALL;
+    sf->tx_size_search_method = frame_is_intra_only(cm) ? USE_FULL_RD
+                                                        : USE_LARGESTALL;
 
     if (MIN(cm->width, cm->height) >= 720)
       sf->disable_split_mask = cm->show_frame ? DISABLE_ALL_SPLIT