The non-SEF URL always exists. SEF URLs are basically only a visual layer above the non-SEF ones. Thus it makes sense to use the non-SEF URLs in the cases where it's not visible to the user. Like for AJAX requests.
Is there a bug you wanted to fix or did you just stumble over this code and wanted to change it?

maybe problem with the relative path, so better just change to JURI::base(true) . '/index.php',
as @Bakual said here no sense to use JRoute

Fedik has it right. I'll fix the patch to not use JRouter.

@CamJN do not forget make the post with the problem description on the Issue tracker http://joomlacode.org/gf/project/joomla/tracker/?action=TrackerItemBrowse&tracker_id=8103 and link this pull request

old ones:
http://joomlacode.org/gf/project/joomla/tracker/?action=TrackerItemEdit&tracker_item_id=27299&start=0
http://joomlacode.org/gf/project/joomla/tracker/?action=TrackerItemEdit&tracker_item_id=21129&start=0
http://joomlacode.org/gf/project/joomla/tracker/?action=TrackerItemEdit&tracker_item_id=25449&start=0
new one:
http://joomlacode.org/gf/project/joomla/tracker/?action=TrackerItemEdit&tracker_item_id=33042&start=0

Just asking but if you use JURI::base(true), do you even need the index.php part?

You won't need the index.php part.

On Mon, Dec 23, 2013 at 1:47 PM, Thomas Hunziker
notifications@github.comwrote:

Just asking but if you use JURI::base(true), do you even need the
index.php part?

—
Reply to this email directly or view it on GitHub#2718 (comment)
.

@CamJN please return index.php back.
@Bakual yes it need, especially on frontend.
By default Apache have the 'index' ordering index.html then index.php, and some people use this for 'Site intro' (if some holiday, event or for other purpose) trick.
So if you have index.html and remove index.php from the keepalive, then Apache will return content from index.html and keepalive will not do job for which it was created.

Interesting usecase
Doesn't hurt to have the index.php there of course.

@CamJN This PR has some conflicts. Can you please rebase it with staging?
I'm going to close it since it's currently targeted at an old branch. Please create a new PR after you have rebased your branch and add the new PR to the tracker. Hopefully it will get tested then.