Change TypeConverter<X,Y>::ConvertFrom and ConvertTo into a single symmetric

mojo/services/public/cpp/view_manager/lib/view_manager_client_impl.cc

Index: mojo/services/public/cpp/view_manager/lib/view_manager_client_impl.cc
diff --git a/mojo/services/public/cpp/view_manager/lib/view_manager_client_impl.cc b/mojo/services/public/cpp/view_manager/lib/view_manager_client_impl.cc
index ec4ec6125e49e64a32221d8882b6c50eecc8f67a..88b3548b021637c4b421c3e50180f54c2b07e6ab 100644
--- a/mojo/services/public/cpp/view_manager/lib/view_manager_client_impl.cc
+++ b/mojo/services/public/cpp/view_manager/lib/view_manager_client_impl.cc
@@ -301,7 +301,7 @@ void ViewManagerClientImpl::OnEmbed(
   if (!connected_) {
     connected_ = true;
     connection_id_ = connection_id;
-    creator_url_ = TypeConverter<String, std::string>::ConvertFrom(creator_url);
+    creator_url_ = String::From(creator_url);
   } else {
     DCHECK_EQ(connection_id_, connection_id);
     DCHECK_EQ(creator_url_, creator_url);