Remove enable_modernize_visual_update_on_tablet from tests

Change-Id: Iec06a14e5dd4599f019d06b8238c7e564c59888a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5403857


Reviewed-by: Tomasz Wiszkowski <ender@google.com>
Commit-Queue: Gang Wu <gangwu@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1280323}