Bug: when view options setting imports

[Justinidlerz]

When i setting view options imports key, like so:

app.set('view options', {
  debug: process.env.NODE_ENV !== 'production',
  imports:  {
    $manifest: filename => manifest[filename] || filename
  })
});

throw a error $escape not a function

You must extend defaults options can fix it.

app.set('view options', {
  debug: process.env.NODE_ENV !== 'production',
  imports: extend({}, artTemplate.defaults.imports, {
    $manifest: filename => manifest[filename] || filename
  })
});

[Justinidlerz]

还是老问题，但这次如果进行extend也报错了

[aui]

重构的时候产生了新的 BUG，v4.9.1 已经修复