chore: Finally drop pre Qt6.8 theme icon workarounds

- https://bugreports.qt.io/browse/QTBUG-135159
- https://codereview.qt-project.org/c/qt/qtbase/+/634907

Author: ManuelSchneid3r

CMakeLists.txt

@@ -243,12 +243,8 @@ elseif(UNIX)  # assume xdg
     )
     list(APPEND LIB_SRC
         src/platform/unix/signalhandler.cpp
-        src/platform/xdg/iconlookup.cpp
-        src/platform/xdg/iconlookup.h
         src/platform/xdg/platform.cpp
         src/platform/xdg/desktopentryparser.cpp
-        src/platform/xdg/themefileparser.cpp
-        src/platform/xdg/themefileparser.h
     )
 endif()
 

src/icon/themeicon.cpp

@@ -1,24 +1,12 @@
-// SPDX-FileCopyrightText: 2022-2025 Manuel Schneider
+// SPDX-FileCopyrightText: 2022-2026 Manuel Schneider
 
 #include "themeicon.h"
-#if defined(Q_OS_UNIX) && !defined(Q_OS_MAC)
-#include "iconlookup.h"
-#endif
 using namespace Qt::StringLiterals;
 using namespace albert;
 using namespace std;
 
-
 ThemeIcon::ThemeIcon(const QString &name)
-    : QIconIcon(
-        // https://bugreports.qt.io/browse/QTBUG-135159
-        // https://codereview.qt-project.org/c/qt/qtbase/+/634907
-#if QT_VERSION > 0x060800
-        QIcon::fromTheme(name)
-#else
-        QIcon(XDG::IconLookup::iconPath(name))
-#endif
-    )
+    : QIconIcon(QIcon::fromTheme(name))
     , name_(name)
 {}
 
@@ -30,4 +18,3 @@ QString ThemeIcon::scheme() { return u"xdg"_s; }
 
 unique_ptr<ThemeIcon> ThemeIcon::fromUrl(const QString &url)
 { return make_unique<ThemeIcon>(url.mid(scheme().size() + 1 )); }
-