[Media Router] Wiring for searching route providers for new sinks.

chrome/browser/media/router/media_router_metrics.h

Index: chrome/browser/media/router/media_router_metrics.h
diff --git a/chrome/browser/media/router/media_router_metrics.h b/chrome/browser/media/router/media_router_metrics.h
index dbdeb1989ee74c1ff3e10d5c6a9631a4647dc8f3..877b9454b206caf0408861f79b58f41dfa04e412 100644
--- a/chrome/browser/media/router/media_router_metrics.h
+++ b/chrome/browser/media/router/media_router_metrics.h
@@ -41,9 +41,10 @@ enum class MediaRouteProviderWakeReason {
   CONNECTION_ERROR = 12,
   REGISTER_MEDIA_ROUTE_PROVIDER = 13,
   CONNECT_ROUTE_BY_ROUTE_ID = 14,
+  SEARCH_SINKS = 15,
 
   // NOTE: Add entries only immediately above this line.
-  TOTAL_COUNT = 15
+  TOTAL_COUNT = 16
 };
 
 // The possible outcomes from a route creation response.