The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/bd693b9640181dcad2c8cda05ad82bcfd46a8398

commit bd693b9640181dcad2c8cda05ad82bcfd46a8398
Author: olivierrobin <olivierrobin@chromium.org>
Date: Mon Feb 20 16:49:17 2017

[IOS Reading List] Change handling of distillation error.

New behavior:
- No single error is permanent.
- After 6 tries, we report permanent error and do not retry.

BUG= 693503 

Review-Url: https://codereview.chromium.org/2703773002
Cr-Commit-Position: refs/heads/master@{#451638}

[modify] https://crrev.com/bd693b9640181dcad2c8cda05ad82bcfd46a8398/ios/chrome/browser/reading_list/reading_list_download_service.cc
[modify] https://crrev.com/bd693b9640181dcad2c8cda05ad82bcfd46a8398/ios/chrome/browser/reading_list/url_downloader.cc
[modify] https://crrev.com/bd693b9640181dcad2c8cda05ad82bcfd46a8398/ios/chrome/browser/reading_list/url_downloader.h

@olivierrobin, What is a good way to test this? all test pages that I have are actually being handled correctly. I am not able to get an entry with exclamation mark icon.

I can actually verify that I've seen this grey exclamation mark icon in some cases when I add to reading list right before losing network. I think it's fine to mark this as verified. Thanks, Sharon!

I have seen the badge on couple of sites. Linked below the screenshot.
Device: iPhone7, iOS:10.3.2 beta#3
M60.0.3073.0 Canary

https://drive.google.com/file/d/0B-xmXLQhjeKuR2VXU3pSUzNQSFU/view