For `PUT` requests, `Response.url` is `undefined` for IE 11 and Edge <= 13

[michaelglass]

We saw this in production against
IE 11, Edge 12, Edge 13, seems fixed on Edge 14
on
Windows 7, 8.1, and Windows 10,

Here's a test case:
https://github.com/michaelglass/repro-ie-put-bug/

The result of the Debug.log in the test case above yields:

{ status = { code = 200, message = "" }
, headers = Dict.fromList [("\ncontent-type","application/json; charset=utf-8")]
, url = <internal structure>
, body = "{\"updatedAt\":\"2018-04-05T08:48:49.587Z\"}" 
}

grabbing the output of the raw xhr request from toResponse(xhr) yields:

{
   0: <Unable to get property 'message' of undefined or null reference>,
   __proto__: { },
   DONE: 4,
   HEADERS_RECEIVED: 2,
   LOADING: 3,
   msCaching: "auto",
   onabort: null,
   onerror: null,
   onload: null,
   onloadend: null,
   onloadstart: null,
   onprogress: null,
   onreadystatechange: null,
   ontimeout: null,
   OPENED: 1,
   readyState: 4,
   response: "{"updatedAt":"2018-04-05T08:51:32.200Z"}",
   responseBody: <String expected>,
   responseText: "{"updatedAt":"2018-04-05T08:51:32.200Z"}",
   responseType: "text"
}

I couldn't get Ellie to work with IE11 but the bug reproduces fine from elm reactor.

(tagging @stoeffel as he helped here)

[process-bot]

Thanks for the issue! Make sure it satisfies this checklist. My human colleagues will appreciate it!

Here is what to expect next, and if anyone wants to comment, keep these things in mind.