[Kickoff] Move DragHelper to FullRepresentation

It is only accessed from items within it (KickoffItem), there's no need to create it initially.

Differential Revision: https://phabricator.kde.org/D9314

applets/kickoff/package/contents/ui/FullRepresentation.qml

@@ -58,6 +58,13 @@ Item {
         }
     }
 
+    Kicker.DragHelper {
+        id: dragHelper
+
+        dragIconSize: units.iconSizes.medium
+        onDropped: kickoff.dragSource = null
+    }
+
     Kicker.AppsModel {
         id: rootModel
 

applets/kickoff/package/contents/ui/Kickoff.qml

@@ -75,13 +75,6 @@ Item {
 
     property Item dragSource: null
 
-    Kicker.DragHelper {
-        id: dragHelper
-
-        dragIconSize: units.iconSizes.medium
-        onDropped: kickoff.dragSource = null
-    }
-
     Kicker.ProcessRunner {
         id: processRunner;
     }