wifi.proto score experiment id

Bug: 79482323
Test: unit tests
Change-Id: I293f5acdfdc2f88515a77e6aeff7b704ffcf1dd8
diff --git a/proto/src/wifi.proto b/proto/src/wifi.proto
index 9ff8e7d..bf9ccb8 100644
--- a/proto/src/wifi.proto
+++ b/proto/src/wifi.proto
@@ -453,6 +453,10 @@
 
   // Number of times the firmware picked a SoftAp channel not satisfying user band preference.
   optional int32 num_soft_ap_user_band_preference_unsatisfied = 116;
+
+  // Identifier for experimental scoring parameter settings.
+  optional string score_experiment_id = 117;
+
 }
 
 // Information that gets logged for every WiFi connection.