treeForAddon(tree) {
    if (!tree) {
      return tree;
    }

    let addonTree = this.compileAddon(tree);
    let stylesTree = this.compileStyles(this._treeFor('addon-styles'));

    return mergeTrees([addonTree, stylesTree], { annotation: `Addon#treeForAddon(${this.name})` });
  }
Returns a tree for this addon

    @public
    @method treeForAddon
    @param {Tree} tree
    @return {Tree} Addon file tree

    @example
    ```js
    treeForAddon() {
      let emberVersion = new VersionChecker(this.project).for('ember-source');
      let shouldUsePolyfill = emberVersion.lt('4.5.0-alpha.4');

      if (shouldUsePolyfill) {
        return this._super.treeForAddon.apply(this, arguments);
      }
    }
    ```