[Media Router] Adds return value to mojo MediaRouteProvider::TerminateRoute.

chrome/browser/media/router/mojo/media_router_mojo_metrics.cc

Index: chrome/browser/media/router/mojo/media_router_mojo_metrics.cc
diff --git a/chrome/browser/media/router/mojo/media_router_mojo_metrics.cc b/chrome/browser/media/router/mojo/media_router_mojo_metrics.cc
index 6937f32ad36b9ff8b637e0718bce95347e4a8a7e..5c9b291977ed9c17c1fa8e36516bc55dc9a78c06 100644
--- a/chrome/browser/media/router/mojo/media_router_mojo_metrics.cc
+++ b/chrome/browser/media/router/mojo/media_router_mojo_metrics.cc
@@ -50,6 +50,15 @@ void MediaRouterMojoMetrics::RecordMediaRouteProviderWakeup(
 }
 
 // static
+void MediaRouterMojoMetrics::RecordMediaRouteProviderTerminateRoute(
+    RouteRequestResult::ResultCode result_code) {
+  DCHECK_LT(result_code, RouteRequestResult::ResultCode::TOTAL_COUNT);
+  UMA_HISTOGRAM_ENUMERATION(
+      "MediaRouter.Provider.TerminateRoute.Result", result_code,
+      RouteRequestResult::ResultCode::TOTAL_COUNT);
+}
+
+// static
 MediaRouteProviderVersion MediaRouterMojoMetrics::GetMediaRouteProviderVersion(
     const base::Version& extension_version,
     const base::Version& browser_version) {