Deprecated unused TRANSIT_DOCK_TASK_FROM_RECENTS transition.

Test: existing tests pass.
Change-Id: I1ad4893c2153ffec1e268643135df8304bcca738
diff --git a/stats/enums/view/enums.proto b/stats/enums/view/enums.proto
index 0172e78..a601abe 100644
--- a/stats/enums/view/enums.proto
+++ b/stats/enums/view/enums.proto
@@ -60,7 +60,7 @@
     TRANSIT_TASK_OPEN_BEHIND = 16;
     TRANSIT_TASK_IN_PLACE = 17;
     TRANSIT_ACTIVITY_RELAUNCH = 18;
-    TRANSIT_DOCK_TASK_FROM_RECENTS = 19;
+    TRANSIT_DOCK_TASK_FROM_RECENTS = 19 [deprecated=true];
     TRANSIT_KEYGUARD_GOING_AWAY = 20;
     TRANSIT_KEYGUARD_GOING_AWAY_ON_WALLPAPER = 21;
     TRANSIT_KEYGUARD_OCCLUDE = 22;