Give `description`.
Give `description`.

Without a `description` the slow tree graph uses `Class` as the name for this tree (since that is its `constructor.name`).
chadhietala/broccoli-es6modules,joefiorini/broccoli-es6modules,stefanpenner/broccoli-es6modules,ember-cli/broccoli-es6modules,joliss/broccoli-es6modules