smsapp: Use Kirigami.ShadowedRectangle instead of DropShadow

Deprecated, allows to remove Qt5Compat import.

smsapp/qml/SendingArea.qml

@@ -9,7 +9,6 @@ import QtCore
 import QtQuick.Controls as Controls
 import QtQuick.Layouts
 import org.kde.kirigami as Kirigami
-import Qt5Compat.GraphicalEffects
 import QtQuick.Dialogs
 import org.kde.kdeconnect.sms
 
@@ -41,22 +40,21 @@ ColumnLayout {
         }
     }
 
+    Kirigami.ShadowedRectangle {
+        implicitHeight: sendingArea.height
+        implicitWidth: sendingArea.width
+        color: "transparent"
+        shadow {
+            size: Math.round(Kirigami.Units.largeSpacing*1.5)
+            color: Kirigami.Theme.disabledTextColor
+        }
+
         Controls.Pane {
             id: sendingArea
             enabled: page.deviceConnected
-        layer.enabled: sendingArea.enabled
-        layer.effect: DropShadow {
-            verticalOffset: 1
-            color: Kirigami.Theme.disabledTextColor
-            samples: 20
-            spread: 0.3
-        }
-        Layout.fillWidth: true
+            implicitWidth: root.width
             padding: 0
             wheelEnabled: true
-        background: Rectangle {
-            color: Kirigami.Theme.backgroundColor
-        }
 
             RowLayout {
                 anchors.fill: parent
@@ -202,5 +200,9 @@ ColumnLayout {
                     }
                 }
             }
+
         }
+
+    }
+
 }