Hide windows title doesn't work with Qt Applications

[pbui]

(1) Issue/Bug Description:

Recent commit 3386f42 has introduced a regression with Qt applications. With this commit, Qt applications such as OBS studio, Zoom, and VLC no longer hide their window titles if this setting is enabled.

(2) Steps to reproduce (if you know):

Disable Show Window Titles and then start a Qt application such as OBS studio, Zoom, or VLC.

(3) Expected behavior:

The window title should be hidden as it was before this commit.

(4) Distribution (run cat /etc/os-release):

NAME="Pop!_OS"
VERSION="22.04 LTS"
ID=pop
ID_LIKE="ubuntu debian"
PRETTY_NAME="Pop!_OS 22.04 LTS"
VERSION_ID="22.04"
HOME_URL="https://pop.system76.com"
SUPPORT_URL="https://support.system76.com"
BUG_REPORT_URL="https://github.com/pop-os/pop/issues"
PRIVACY_POLICY_URL="https://system76.com/privacy"
VERSION_CODENAME=jammy
UBUNTU_CODENAME=jammy
LOGO=distributor-logo-pop-os

(5) Gnome Shell version:

42.5

(6) Pop Shell version (run apt policy pop-shell or provide the latest commit if building locally):

pop-shell:
  Installed: 1.1.0~1698186494~22.04~3386f42
  Candidate: 1.1.0~1698186494~22.04~3386f42
  Version table:
 *** 1.1.0~1698186494~22.04~3386f42 1001
       1001 http://apt.pop-os.org/release jammy/main amd64 Packages
       1001 http://apt.pop-os.org/release jammy/main i386 Packages
        100 /var/lib/dpkg/status

(7) Where was Pop Shell installed from:

Pop!_OS Apt repository.

(8) Monitor Setup (2 x 1080p, 4K, Primary(Horizontal), Secondary(Vertical), etc):

1080p, Primary (Horizontal)

(9) Other Installed/Enabled Extensions:

(10) Other Notes:

I made my intial comments here: #1661 (comment)

[jacobgkau]

Confirmed this regression with KWrite. The regression testing document currently only suggests LibreOffice Writer and the Pop!_Shell Shortcuts dialog for testing this option; I also checked Evolution while testing #1661. Looks like we need to add a checkbox for a Qt app.

We will need to either revert #1661 or gate the change behind a GNOME version check.