fix qml break for kf5 <= 5.68

BUG:426119

containment/package/contents/ui/colorizer/CustomBackground.qml

@@ -113,14 +113,9 @@ Item{
         id: kirigamiRect
         anchors.fill: painter
         active: root.kirigamiLibraryIsFound && main.shadowSize>0
-        sourceComponent: KirigamiShadowedRectangle {
-            radius: painter.radius
-            color: "transparent"
-            shadow.size: main.shadowSize
-            //! WORKAROUND, plasma theme shadow color compared to KirigamiShadowedRectangle drawn shadow has an alpha difference. This way
-            //! we make sure that when the user uses the same shadow size with plasma theme original one we draw the same shadow compared visually
-            shadow.color: Qt.rgba(main.shadowColor.r, main.shadowColor.g, main.shadowColor.b, Math.min(1, 0.336 + main.shadowColor.a))
-        }
+        //! this "source" approach is needed in order for KF5<=5.68 to load Latte correctly with no
+        //! qml breakage because Kirigami2.ShadowedRectangle is not present
+        source: root.kirigamiLibraryIsFound ? "KirigamiShadowedRectangle.qml" : "NormalRectangle.qml"
     }
 
     Rectangle{

containment/package/contents/ui/colorizer/KirigamiShadowedRectangle.qml

@@ -1,5 +1,5 @@
 /*
-*  Copyright 2018 Michail Vourlakos <mvourlakos@gmail.com>
+*  Copyright 2020 Michail Vourlakos <mvourlakos@gmail.com>
 *
 *  This file is part of Latte-Dock
 *
@@ -25,4 +25,10 @@ import org.kde.plasma.core 2.0 as PlasmaCore
 import org.kde.kirigami 2.12 as Kirigami
 
 Kirigami.ShadowedRectangle {
+    radius: painter.radius
+    color: "transparent"
+    shadow.size: main.shadowSize
+    //! WORKAROUND, plasma theme shadow color compared to KirigamiShadowedRectangle drawn shadow has an alpha difference. This way
+    //! we make sure that when the user uses the same shadow size with plasma theme original one we draw the same shadow compared visually
+    shadow.color: Qt.rgba(main.shadowColor.r, main.shadowColor.g, main.shadowColor.b, Math.min(1, 0.336 + main.shadowColor.a))
 }

containment/package/contents/ui/colorizer/NormalRectangle.qml

@@ -0,0 +1,25 @@
+/*
+*  Copyright 2020 Michail Vourlakos <mvourlakos@gmail.com>
+*
+*  This file is part of Latte-Dock
+*
+*  Latte-Dock is free software; you can redistribute it and/or
+*  modify it under the terms of the GNU General Public License as
+*  published by the Free Software Foundation; either version 2 of
+*  the License, or (at your option) any later version.
+*
+*  Latte-Dock is distributed in the hope that it will be useful,
+*  but WITHOUT ANY WARRANTY; without even the implied warranty of
+*  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+*  GNU General Public License for more details.
+*
+*  You should have received a copy of the GNU General Public License
+*  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+import QtQuick 2.7
+
+Rectangle {
+    visible: false
+}
+