HttpRequest.getString() recommended by docs for fetching JSON, but demands "text/" mime response

[Valloric]

Headline doc entry for HttpRequest: https://api.dartlang.org/apidocs/channels/stable/dartdoc-viewer/dart:html.HttpRequest

> The simplest way to get the contents of a text file, such as a JSON-formatted file, is with getString. [example follows]

Docs for getString (same page):

> The server response must be a text/ mime type for this request to succeed.

Official mimetype for JSON: http://en.wikipedia.org/wiki/JSON#MIME_type

> The official MIME type for JSON text is "application/json".

These three facts put together make zero sense. Either getString should work with responses that aren't "text/" (makes the most sense), or the docs shouldn't recommend the use of this method for JSON.

[kasperl]

Added Area-Library, Library-Html, Triaged labels.

[Valloric]

This Dart tutorial also uses getString to fetch JSON data: https://www.dartlang.org/docs/tutorials/fetchdata/

[alan-knight]

The docs for getString are incorrect. It will happily succeed even if the content type is image/png and give you a bunch of characters. I'm not sure which encoding it's applying, but it should be fine for JSON text.

---

Removed Type-Defect label.
Added Type-Documentation, Accepted labels.

[dvorapa]

I'm currently getting error to console as getString now expects XML somehow by default

[dvorapa]

It seems all is either responseType fault or browser bug. See #47743 where I describe my issue (pretty similar though)