Revert "WebApps: Change default for preinstalled D/S/S/D to standalone tabbed apps"

This reverts commit b7c7cb59be59fafb035f62566170cbc0b663a07b.

Reason for revert: PreinstalledWebAppWindowExperimentBrowserTest.* consistently failing.

Sample failure: https://ci.chromium.org/ui/p/chrome/builders/ci/linux-chromeos-chrome/36959/test-results

Original change's description:
> WebApps: Change default for preinstalled D/S/S/D to standalone tabbed apps
>
> Previously when Google Docs, Sheets, Slides, and Drive were
> preinstalled, they were set to open in a browser tab. Now that tabbed
> web apps are launched, D/S/S/D are moving to use a tabbed web app when
> installed. This CL updates the default to match (otherwise the
> DisplayMode will change on app update later).
>
> Excludes managed devices/profiles from the change to reduce disruption
> in enterprise environments. Will do a follow-up CL with some tests for
> the managed device detection.
>
> Doesn't currently set a home/new tab configuration, so tabbed editors
> will not have a home tab, and use the start_url for new tabs. Will
> follow up with a fix for that.
>
> Launch: launch/4273092
> Bug: b/298288181
> Change-Id: I1a8eb02c9cb3045e442d86195fed4cc9e093dabb
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4938531
> Auto-Submit: Glen Robertson <glenrob@chromium.org>
> Commit-Queue: Alan Cutter <alancutter@chromium.org>
> Reviewed-by: Alan Cutter <alancutter@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#1219340}

Bug: b/298288181
Change-Id: I82f2e2e8b823d674d6c25a4cef27b043c10c0155
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5004012
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Owners-Override: Monica Basta <msalama@chromium.org>
Commit-Queue: Monica Basta <msalama@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1219398}