GitLab

Delayed Warnings feature delays certain interstitials until the user
presses a key. It presently ignores ESC key as it can be used to exit
from fullscreen mode.

The user can also use browser shortcuts such as Control+T to open a
new tab. This CL allows modifier keys (Control, Alt etc) so that browser
shortcuts don't show the interstitial.

There are two exceptions made by the CL:
- Shift pressed with other character keys still show the interstitial as
the user may be typing uppercase letters.
- Ctrl+C and Ctrl+V still show the interstitial as they are shortcuts
for copy & paste.

Bug: 1131149
Change-Id: I5d3532b9296beef783e01e18d14e0b7a53309fe2
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2425206Reviewed-by: Daniel Rubery <drubery@chromium.org>
Reviewed-by: Emily Stark <estark@chromium.org>
Commit-Queue: Mustafa Emre Acer <meacer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#809848}