[sync] SYNC_AUTH_ERROR in logs when running sync_integration_tests

components/sync/engine_impl/net/server_connection_manager.cc

Index: components/sync/engine_impl/net/server_connection_manager.cc
diff --git a/components/sync/engine_impl/net/server_connection_manager.cc b/components/sync/engine_impl/net/server_connection_manager.cc
index 9aa63e8ae26abefec825ddf39db4f91a4dcc2131..76e62468045ba223dfb088b5d65edc9a3e45b279 100644
--- a/components/sync/engine_impl/net/server_connection_manager.cc
+++ b/components/sync/engine_impl/net/server_connection_manager.cc
@@ -266,7 +266,8 @@ bool ServerConnectionManager::PostBufferToPath(PostBufferParams* params,
   if (auth_token.empty() || auth_token == "credentials_lost") {
     params->response.server_status = HttpResponse::SYNC_AUTH_ERROR;
     // Print a log to distinguish this "known failure" from others.
-    LOG(WARNING) << "ServerConnectionManager forcing SYNC_AUTH_ERROR";
+    DVLOG(1) << "ServerConnectionManager forcing SYNC_AUTH_ERROR due to missing"
+                " auth token";
     return false;
   }