wallpaper protocols

[justforlxz]

• Add preview wallpaper function.
• Add set wallpaper to lockscreen
• Add set wallpaper to screen
• Accepts parent_window as the client ID of the lookup caller
• Set wallpaper color type / query for color type output

https://flatpak.github.io/xdg-desktop-portal/docs/doc-org.freedesktop.portal.Wallpaper.html

[zorowk]

this has been done
#258

there are two questions :

1. treeland-wallpaper cannot use qApp->screens to get the correct output name

QWaylandScreen::QWaylandScreen(QWaylandDisplay *waylandDisplay, int version, uint32_t id)
    : QtWayland::wl_output(waylandDisplay->wl_registry(), id, qMin(version, 3))
    , m_outputId(id)
    , mWaylandDisplay(waylandDisplay)
    , mOutputName(QStringLiteral("Screen%1").arg(id))

now treeland-wallpaper run treeland evironment get output name is Screen25

the client does not execute initxdgoutput, normally the following stack should be called

1   QtWaylandClient::QWaylandScreen::initXdgOutput             qwaylandscreen.cpp 
2   QtWaylandClient::QWaylandScreen::QWaylandScreen            qwaylandscreen.cpp 
3   QtWaylandClient::QWaylandIntegration::createPlatformScreen qwaylandintegration.cpp 
4   QtWaylandClient::QWaylandDisplay::registry_global          qwaylanddisplay.cpp
5   QtWayland::wl_registry::handle_global                      qwayland-wayland.cpp
... <More>

2. treeland call QuickPersonalizationManagerPrivate::loadWallpaperSettings() load all output background
   It will traverse qApp->screens() but this time QWlrootsIntegration::addScreen(WOutput *output) has not yet put the screen data into the qt container.

[zorowk]

f15e0ba this will solve treeland-wallpaper problem