Use stricter type checking in UMA_HISTOGRAM_ENUMERATION

components/sync/driver/startup_controller.cc

Index: components/sync/driver/startup_controller.cc
diff --git a/components/sync/driver/startup_controller.cc b/components/sync/driver/startup_controller.cc
index 6131e2807dbc13b1659f102e3310295851674a3a..f465a7c85e81ecfd45922369207f238ef2aa4431 100644
--- a/components/sync/driver/startup_controller.cc
+++ b/components/sync/driver/startup_controller.cc
@@ -186,8 +186,10 @@ void StartupController::OnDataTypeRequestsSyncStartup(ModelType type) {
   // Measure the time spent waiting for init and the type that triggered it.
   // We could measure the time spent deferred on a per-datatype basis, but
   // for now this is probably sufficient.
+  // TODO(wychen): enum uma should be strongly typed. crbug.com/661401
   UMA_HISTOGRAM_ENUMERATION("Sync.Startup.TypeTriggeringInit",
-                            ModelTypeToHistogramInt(type), MODEL_TYPE_COUNT);
+                            ModelTypeToHistogramInt(type),
+                            static_cast<int>(MODEL_TYPE_COUNT));
   if (!start_up_time_.is_null()) {
     RecordTimeDeferred();
     UMA_HISTOGRAM_ENUMERATION("Sync.Startup.DeferredInitTrigger",