framework/web/View.php
protected function registerAssetFiles($name)
    {
        if (!isset($this->assetBundles[$name])) {
            return;
        }
        $bundle = $this->assetBundles[$name];
        if ($bundle) {
            foreach ($bundle->depends as $dep) {
                $this->registerAssetFiles($dep);
            }
            $bundle->registerAssetFiles($this);
        }
        unset($this->assetBundles[$name]);
    }
protected function registerAssetFiles($name)
    {
        if (!isset($this->assetBundles[$name])) {
            return;
        }
        $bundle = $this->assetBundles[$name];
        if ($bundle) {
            foreach ($bundle->depends as $dep) {
                $this->registerAssetFiles($dep);
            }
            $bundle->registerAssetFiles($this);
        }
        unset($this->assetBundles[$name]);
    }
Registers all files provided by an asset bundle including depending bundles files.
Removes a bundle from [[assetBundles]] once files are registered.
@param string $name name of the bundle to register