Use stricter type checking in UMA_HISTOGRAM_ENUMERATION

components/sync_bookmarks/bookmark_model_associator.cc

Index: components/sync_bookmarks/bookmark_model_associator.cc
diff --git a/components/sync_bookmarks/bookmark_model_associator.cc b/components/sync_bookmarks/bookmark_model_associator.cc
index c710dbc1b7897141c82f98996298d4b2e356d97b..a490d4deced304ce57bfb4471c41dbd0b78b77f2 100644
--- a/components/sync_bookmarks/bookmark_model_associator.cc
+++ b/components/sync_bookmarks/bookmark_model_associator.cc
@@ -963,9 +963,10 @@ syncer::SyncError BookmarkModelAssociator::CheckModelSyncState(
     if (native_version == sync_version) {
       context->set_native_model_sync_state(IN_SYNC);
     } else {
+      // TODO(wychen): enum uma should be strongly typed. crbug.com/661401
       UMA_HISTOGRAM_ENUMERATION("Sync.LocalModelOutOfSync",
                                 ModelTypeToHistogramInt(syncer::BOOKMARKS),
-                                syncer::MODEL_TYPE_COUNT);
+                                static_cast<int>(syncer::MODEL_TYPE_COUNT));
 
       // Clear version on bookmark model so that we only report error once.
       bookmark_model_->SetNodeSyncTransactionVersion(