The category was dropped because there isn't a firm line between them and
other limited-use scripts. It can well be that one of the other limited-use
scripts would be a higher priority than the formerly aspirational scripts,
so they would need to be all prioritized.

Mark

Thank you, Mark. 

In the meantime, what do you think of dropping Mongolian? It seems to make little sense to use Mongolian in domain names (regardless of its status - aspirational or limited).   

ping markdavis@ to reply to the question in comment #2

Mongolian is not a high priority, given its usage patterns. So I'd have
nothing against dropping it for now. On the other hand, it is not likely to
be confusable with anything...

Mark

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/afca0a393f23f0b7ef18d8c3d05e166c3012606d

commit afca0a393f23f0b7ef18d8c3d05e166c3012606d
Author: Jungshik Shin <jshin@chromium.org>
Date: Wed Oct 25 00:13:47 2017

Disallow 5 aspirational scripts in IDN display

UTS 31 (http://www.unicode.org/reports/tr31/#Aspirational_Use_Scripts )
used to list 5 scripts in Table 6 as 'aspirational scripts', but it
deprecated the category and moved 5 scripts to Table 7 for limited use
scripts.

Given this, there's no basis to treat those 5 scripts differently from
other limited use scripts. Note that Mozilla stopped allowding those 5
scripts in IDN display a while ago.

This is also necessary for updating ICU to version 60.

Bug:  724968 , 766816 
Test: components_unittests --gtest_filter=*IDN*
Change-Id: I32e7d030107ef90dd3b80f64849ab7398ae98985
Reviewed-on: https://chromium-review.googlesource.com/731871
Reviewed-by: Brett Wilson <brettw@chromium.org>
Commit-Queue: Jungshik Shin <jshin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#511316}
[modify] https://crrev.com/afca0a393f23f0b7ef18d8c3d05e166c3012606d/components/url_formatter/idn_spoof_checker.cc
[modify] https://crrev.com/afca0a393f23f0b7ef18d8c3d05e166c3012606d/components/url_formatter/url_formatter_unittest.cc