Spanish version of header example is missing translation for English

[bernardwang]

Note: This is not actually a bug in production—just with the example.

The English version of the menu correctly shows Español for the language-switching link:

But when switching to Spanish, the header.english translation is missing:

I think this may have to do with the fact that it is originally loaded in English, and there may be some sort of key caching going on inside i18n. We actually use two different keys (header.english and header.español).