Typically, it shouldn't, since this is a app-specific string. We package with a default value, since we can't have a null type. However, apps have their own value in strings.xml, including our own sample apps. In the rare case that someone wants to use this default value, I will run through some upgrade testing to ensure the transition is seamless (an end-user should not have any impact). If there is such an impact, its probably best to not fix the typo. Either way, I don't think this should be documented, since its completely internal.