The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/842b2bad2021a93292f791f84cfba1e459343e7d

commit 842b2bad2021a93292f791f84cfba1e459343e7d
Author: Lei Zhang <thestig@chromium.org>
Date: Tue Apr 24 20:48:36 2018

PDF: Fix "Select all" context menu item in forms on Mac.

There is a pre-existing bug on Mac where Control + A performs "Select
all" instead of Command + A. The equivalent context menu item just sends
the keystroke to perform "Select all". As such, when it tried to do the
right thing and use the Command modifier, "Select all" does not actually
work.

To fix this quickly, just make the context menu item send Control + A.
Of course this is not ideal, but making Command + A perform "Select all"
is harder than it appears.

BUG= 834735 ,836074

Change-Id: I2c8201772d7e901984c427d0977a1fb899f802b5
Reviewed-on: https://chromium-review.googlesource.com/1025403
Reviewed-by: dsinclair <dsinclair@chromium.org>
Reviewed-by: Bill Budge <bbudge@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>
Cr-Commit-Position: refs/heads/master@{#553264}
[modify] https://crrev.com/842b2bad2021a93292f791f84cfba1e459343e7d/content/renderer/pepper/pepper_plugin_instance_impl.cc

Tested this issue on Mac OS 10.12.6 on the build without fix 68.0.3400 and build with fix 68.0.3406.0 and observed the same behaviour on both the builds.

1. Launched Chrome and navigated to the pdf form http://www.impotsdirects.public.lu/content/dam/acd/fr/formulaires/pers_physiques/2016/100-2016-f-i101.pdf.
2. Entered some text in the text fields and hit Cmd-A keys.
2. Can observe that the text is not selected.
Attached is the screen cast for reference.

thestig@ Request you to check and update on this issue.

Thanks..

Deleted: 836074.mp4 1.1 MB

	836074.mp4 1.1 MB View Download

r553264 was not intended to fix this bug. There's no need to test yet.