The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/2dcd14f9e24eb3ab725b27abce9aa1ee84e96308

commit 2dcd14f9e24eb3ab725b27abce9aa1ee84e96308
Author: Parastoo Geranmayeh <parastoog@google.com>
Date: Fri Jun 01 17:08:39 2018

[Autofill] Placeholder vs. Value Disambiguation.

Problem:
Sometimes the website puts a value on the field by running a JS.
The entered value is practically a placeholder, but is detected as a
value entered by the user. Therefore the autofill will not fill the
field. Another case is where the website prefills the form by the
data from the previous form.

Solution:
On the renderer side, when deciding to autofill or not, only consider
the values entered by the user.

When moving on the autofill dropdown, we'll move from Preview to
Clear Suggested Value. Previously, we would rely on value checking
for clearing a suggested value. Now that we only consider the
values entered by the renderer, we need to distinguish between a
previewed field and an autofilled one. We should only clear the
previewed fields.)

Fixes: www.kohls.com, rakuten.com, oup.com (Prefilled State),
www.shopdisney.com (for clearing)

Bug:  841766 ,  841314 , 841346
Change-Id: If9d8bd4e25982de57ae7d8ec26cb530dce311c7c
Reviewed-on: https://chromium-review.googlesource.com/1069226
Commit-Queue: Parastoo Geranmayeh <parastoog@google.com>
Reviewed-by: Sebastien Seguin-Gagnon <sebsg@chromium.org>
Reviewed-by: Kent Tamura <tkent@chromium.org>
Reviewed-by: Vadym Doroshenko <dvadym@chromium.org>
Reviewed-by: Christos Froussios <cfroussios@chromium.org>
Reviewed-by: Roger McFarlane <rogerm@chromium.org>
Cr-Commit-Position: refs/heads/master@{#563690}
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