Enable Wayland support in Qt, use it if available

com.valvesoftware.SteamLink.yml

@@ -8,7 +8,6 @@ finish_args:
   - --device=all
   - --env=LD_LIBRARY_PATH=/app/lib
   - --env=SDL_GAMECONTROLLERCONFIG_FILE=/var/data/Valve Corporation/SteamLink/controller_map.txt
-  - --env=QT_QPA_PLATFORM=xcb
   - --share=ipc
   - --share=network
   - --socket=pulseaudio
@@ -95,6 +94,29 @@ modules:
           - https://repo.steampowered.com/steamlink/qtsvg-everywhere-src-5.14.1.tar.xz
         sha256: 8540a57312f815f81a45b891b49959d776727fde17579bb6bf1a537996bc9359
 
+  - name: qt5-wayland
+    buildsystem: qmake
+    cleanup:
+      - /bin
+      - /include
+      - /lib/*.a
+      - /lib/*.la
+      - /lib/*.prl
+      - /lib/cmake
+      - /lib/debug
+      - /lib/mkspecs
+      - /lib/pkgconfig
+    sources:
+      - type: archive
+        url: http://download.qt.io/archive/qt/5.14/5.14.1/submodules/qtwayland-everywhere-src-5.14.1.tar.xz
+        mirror-urls:
+          - https://repo.steampowered.com/steamlink/qtwayland-everywhere-src-5.14.1.tar.xz
+        sha256: 2a03b9f554e88c5824ef237c814b3dd45844c022e97be0e091f4a502ca4c9520
+      - type: patch
+        path: patches/org.kde.Sdk/qtwayland-use-gnome-platform-theme-on-gnome-based-desktops.patch
+      - type: patch
+        path: patches/backports/Fix-installing-qtwayland-without-qtquick-or-opengl-s.patch
+
   - name: extra-cmake-modules
     buildsystem: cmake-ninja
     cleanup:

patches/backports/Fix-installing-qtwayland-without-qtquick-or-opengl-s.patch

@@ -0,0 +1,43 @@
+From: Kai Koehne <kai.koehne@qt.io>
+Date: Tue, 3 Mar 2020 16:30:11 +0100
+Subject: Fix installing qtwayland without qtquick or opengl support
+
+Unconditionally generate qwayland-server-qt-texture-sharing-unstable-v1.h,
+even if the header file will not be used. It is listed in syncqt.profile though,
+and because of
+
+  private_headers.CONFIG += no_check_exist
+
+in extensions.pri qmake will unconditionally generate an install rule.
+
+Fixes: QTBUG-82569
+Change-Id: I5125382f1e4fc61936515e045a7e6a4a3c608451
+Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
+Origin: upstream, commit:0f0fbf0a70940379a99618d2069721471e3fc631
+---
+ src/compositor/extensions/extensions.pri | 4 +---
+ 1 file changed, 1 insertion(+), 3 deletions(-)
+
+diff --git a/src/compositor/extensions/extensions.pri b/src/compositor/extensions/extensions.pri
+index 61ab043e..06e3ef9e 100644
+--- a/src/compositor/extensions/extensions.pri
++++ b/src/compositor/extensions/extensions.pri
+@@ -8,6 +8,7 @@ WAYLANDSERVERSOURCES += \
+     ../extensions/touch-extension.xml \
+     ../extensions/qt-key-unstable-v1.xml \
+     ../extensions/qt-windowmanager.xml \
++    ../extensions/qt-texture-sharing-unstable-v1.xml \
+     ../3rdparty/protocol/text-input-unstable-v2.xml \
+     ../3rdparty/protocol/viewporter.xml \
+     ../3rdparty/protocol/scaler.xml \
+@@ -96,9 +97,6 @@ qtHaveModule(quick) {
+         extensions/qwaylandxdgshellintegration.cpp \
+
+     qtConfig(opengl) {
+-        WAYLANDSERVERSOURCES += \
+-            ../extensions/qt-texture-sharing-unstable-v1.xml
+-
+         HEADERS += \
+             extensions/qwltexturesharingextension_p.h
+
+-- 

patches/org.kde.Sdk/qtwayland-use-gnome-platform-theme-on-gnome-based-desktops.patch

@@ -0,0 +1,40 @@
+diff --git a/src/client/qwaylandintegration.cpp b/src/client/qwaylandintegration.cpp
+index 97e0203c..5bee160a 100644
+--- a/src/client/qwaylandintegration.cpp
++++ b/src/client/qwaylandintegration.cpp
+@@ -99,20 +99,26 @@ public:
+
+         if (QGuiApplication::desktopSettingsAware()) {
+             const QByteArray desktopEnvironment = QGuiApplicationPrivate::platformIntegration()->services()->desktopEnvironment();
+-
++            QList<QByteArray> gtkBasedEnvironments;
++            gtkBasedEnvironments << "GNOME"
++                                 << "X-CINNAMON"
++                                 << "UNITY"
++                                 << "MATE"
++                                 << "XFCE"
++                                 << "LXDE";
+             if (desktopEnvironment == QByteArrayLiteral("KDE")) {
+ #if QT_CONFIG(settings)
+                 result.push_back(QStringLiteral("kde"));
+ #endif
+-            } else if (!desktopEnvironment.isEmpty() &&
+-                desktopEnvironment != QByteArrayLiteral("UNKNOWN") &&
+-                desktopEnvironment != QByteArrayLiteral("GNOME") &&
+-                desktopEnvironment != QByteArrayLiteral("UNITY") &&
+-                desktopEnvironment != QByteArrayLiteral("MATE") &&
+-                desktopEnvironment != QByteArrayLiteral("XFCE") &&
+-                desktopEnvironment != QByteArrayLiteral("LXDE"))
++            } else if (gtkBasedEnvironments.contains(desktopEnvironment)) {
++                // prefer the GTK3 theme implementation with native dialogs etc.
++                result.push_back(QStringLiteral("gtk3"));
++                // fallback to the generic Gnome theme if loading the GTK3 theme fails
++                result.push_back(QLatin1String(QGnomeTheme::name));
++            } else if (!desktopEnvironment.isEmpty() && desktopEnvironment != QByteArrayLiteral("UNKNOWN")) {
+                 // Ignore X11 desktop environments
+                 result.push_back(QString::fromLocal8Bit(desktopEnvironment.toLower()));
++            }
+         }
+
+         if (result.isEmpty())
+