layout: Remove redundant background refresh

When using the NVIDIA driver, textures tend to loose their pixels when
suspending. In the past we handled this by figuring out when the NVIDIA
driver was used, and reload the background whenever we noticed we
resumed from suspend.

This shouldn't be needed anymore after
GNOME/mutter!600, as it should
handle this by listening to video-memory-purged signal. Thus remove our
special handling here.

GNOME/gnome-shell!1358
9 jobs for !1358 with wip/remove-redundant-background-refresh in 6 minutes and 38 seconds (queued for 3 seconds)
detached
Status Job ID Name Coverage
  Review
passed #804555
check_commit_log

00:01:47

passed #804558
eslint

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passed #804557
js_check

00:01:13

passed #804560
no_template_check

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passed #804559
potfile_check

00:00:38

 
  Build
passed #804561
build

00:03:33

passed #804562
flatpak
flatpak

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  Test
passed #804563
test

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passed #804564
test-pot

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