Disable screencasting if there's no pipewire 0.3

Hopefully fixes the CI

CMakeLists.txt

@@ -755,9 +755,6 @@ ecm_qt_declare_logging_category(kwin_XWAYLAND_SRCS
 
 set(kwin_WAYLAND_SRCS
    main_wayland.cpp
-   screencast/screencastmanager.cpp
-   screencast/pipewirecore.cpp
-   screencast/pipewirestream.cpp
    tabletmodemanager.cpp
 )
 ecm_qt_declare_logging_category(kwin_WAYLAND_SRCS
@@ -772,9 +769,19 @@ ecm_qt_declare_logging_category(kwin_WAYLAND_SRCS
 )
 
 add_executable(kwin_wayland ${kwin_WAYLAND_SRCS} ${kwin_XWAYLAND_SRCS})
+
+
+if (PipeWire_FOUND)
+    target_sources(kwin_wayland
+        PRIVATE
+        screencast/screencastmanager.cpp
+        screencast/pipewirecore.cpp
+        screencast/pipewirestream.cpp)
+    target_link_libraries(kwin_wayland PkgConfig::PipeWire)
+endif()
+
 target_link_libraries(kwin_wayland
                       kwin
-                      PkgConfig::PipeWire # required for PipewireStream
                       KF5::Crash
 )
 if (HAVE_LIBCAP)

config-kwin.h.cmake

@@ -42,3 +42,5 @@
 #define XCB_ICCCM_WM_STATE_NORMAL 1
 #define XCB_ICCCM_WM_STATE_ICONIC 3
 #endif
+
+#cmakedefine01 PipeWire_FOUND

main_wayland.cpp

@@ -26,7 +26,10 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include "platform.h"
 #include "effects.h"
 #include "tabletmodemanager.h"
+
+#ifdef PipeWire_FOUND
 #include "screencast/screencastmanager.h"
+#endif
 #include "wayland_server.h"
 #include "xwl/xwayland.h"
 
@@ -165,7 +168,9 @@ void ApplicationWayland::performStartup()
     VirtualKeyboard::create(this);
     createBackend();
     TabletModeManager::create(this);
+#ifdef PipeWire_FOUND
     new ScreencastManager(this);
+#endif
 }
 
 void ApplicationWayland::createBackend()

wayland_server.cpp

@@ -458,7 +458,9 @@ bool WaylandServer::init(const QByteArray &socketName, InitializationFlags flags
     m_keyState = m_display->createKeyStateInterface(m_display);
     m_keyState->create();
 
+#ifdef PipeWire_FOUND
     m_screencast = m_display->createScreencastInterface(m_display);
+#endif
 
     return true;
 }