Remove the last traces of Activities data engine

applets/pager/package/contents/ui/main.qml

@@ -25,13 +25,13 @@ import org.kde.plasma.components 2.0 as PlasmaComponents
 import org.kde.kquickcontrolsaddons 2.0 as KQuickControlsAddonsComponents
 import org.kde.draganddrop 2.0
 import org.kde.plasma.private.pager 2.0
+import org.kde.plasma.activityswitcher 1.0 as ActivitySwitcher
 
 MouseArea {
     id: root
 
     property bool isActivityPager: (plasmoid.pluginName === "org.kde.plasma.activitypager")
     property bool vertical: (plasmoid.formFactor === PlasmaCore.Types.Vertical)
-    property var activityDataSource: null
 
     readonly property real aspectRatio: (((pagerModel.pagerItemSize.width * pagerItemGrid.effectiveColumns)
         + ((pagerItemGrid.effectiveColumns * pagerItemGrid.spacing) - pagerItemGrid.spacing))
@@ -47,8 +47,8 @@ MouseArea {
     Plasmoid.preferredRepresentation: Plasmoid.fullRepresentation
     Plasmoid.status: pagerModel.shouldShowPager ? PlasmaCore.Types.ActiveStatus : PlasmaCore.Types.HiddenStatus
 
-    Layout.fillWidth: root.vertical 
-    Layout.fillHeight: !root.vertical 
+    Layout.fillWidth: root.vertical
+    Layout.fillHeight: !root.vertical
 
     property bool dragging: false
     property string dragId
@@ -86,15 +86,7 @@ MouseArea {
     }
 
     function action_showActivityManager() {
-        if (!activityDataSource) {
-            activityDataSource = Qt.createQmlObject('import org.kde.plasma.core 2.0 as PlasmaCore; \
-                PlasmaCore.DataSource { id: dataSource; engine: "org.kde.activities"; \
-                connectedSources: ["Status"] }', root);
-        }
-
-        var service = activityDataSource.serviceForSource("Status")
-        var operation = service.operationDescription("toggleActivityManager")
-        service.startOperationCall(operation)
+        ActivitySwitcher.Backend.toggleActivityManager()
     }
 
     onContainsMouseChanged: {

applets/showActivityManager/package/contents/ui/main.qml

@@ -69,12 +69,6 @@ DND.DropArea {
         ActivitySwitcher.Backend.setDropMode(false);
     }
 
-    PlasmaCore.DataSource {
-        id: dataSource
-        engine: "org.kde.activities"
-        connectedSources: [activeSource]
-    }
-
     PlasmaCore.ToolTipArea {
         id: tooltip
         mainText: i18n("Show Activity Manager")