Fold type arguments in Dart that are in instance creations

Fold type arguments in Dart that are in instance creations, such as "new A<B, C, D>" => "new A<~>"

The new fold is enabled and disabled by the CodeFoldingSettings.COLLAPSE_CUSTOM_FOLDING_REGIONS setting.  My assumption here is that until there are a few custom folding regions, all new folds are set with this setting?  Or should I create a new option for this fold like in the Java support?