Yes, that code looks incorrect to me - Randy landed a cl that removed that requirement and instead added the requirement that {name, domain, path} unique (Or something like that).

A slight complication is that there is code for recovering from duplication of 
(name, domain, path) uniqueness violations (which weren't previously enforced by the store) in CookieMonster::TrimDuplicateCookiesForKey which also somewhat relies on timestamp uniqueness in order to figure out which rows to throw away. 
Arguably this isn't needed with new SQLitePersistentCookieStore, but PersistentStore is kind of pluggable...

I think I have a fix, but it's probably prudent to fix 826322

to fix it first, that is.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/2b0d5b188c142cc1238e66c1069e2eb1d3a6b78d

commit 2b0d5b188c142cc1238e66c1069e2eb1d3a6b78d
Author: Maks Orlovich <morlovich@chromium.org>
Date: Tue Apr 10 19:33:47 2018

CookieMonster: don't enforce ctime uniqueness on load.

This used to be a requirement, but isn't any more, and doing this may cause
us to lose some cookies, which is rude.

Bug:  825222 
Change-Id: I221693e72742e0b520f6f70ba5f0d5f716785c18
Reviewed-on: https://chromium-review.googlesource.com/978384
Commit-Queue: Maks Orlovich <morlovich@chromium.org>
Reviewed-by: Matt Menke <mmenke@chromium.org>
Reviewed-by: Victor Costan <pwnall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#549614}
[modify] https://crrev.com/2b0d5b188c142cc1238e66c1069e2eb1d3a6b78d/net/cookies/cookie_monster.cc
[modify] https://crrev.com/2b0d5b188c142cc1238e66c1069e2eb1d3a6b78d/net/cookies/cookie_monster.h
[modify] https://crrev.com/2b0d5b188c142cc1238e66c1069e2eb1d3a6b78d/net/cookies/cookie_monster_store_test.h
[modify] https://crrev.com/2b0d5b188c142cc1238e66c1069e2eb1d3a6b78d/net/cookies/cookie_monster_unittest.cc