Fix "double"/non-functional scrollbars on ScrollViews

resources/qml/Dialogs/WorkspaceSummaryDialog.qml

@@ -67,7 +67,7 @@ UM.Dialog
 
             ScrollBar.vertical: UM.ScrollBar
             {
-                parent: scroll
+                parent: scroll.parent
                 anchors
                 {
                     top: parent.top

resources/qml/Menus/ConfigurationMenu/ConfigurationListView.qml

@@ -68,7 +68,7 @@ Item
         clip: true
 
         ScrollBar.vertical: UM.ScrollBar {
-            parent: container
+            parent: container.parent
             anchors
             {
                 top: parent.top

resources/qml/Preferences/GeneralPage.qml

@@ -141,7 +141,7 @@ UM.PreferencesPage
         ScrollBar.vertical: UM.ScrollBar
         {
             id: preferencesScrollBar
-            parent: preferencesScrollView
+            parent: preferencesScrollView.parent
             anchors
             {
                 top: parent.top

resources/qml/Preferences/Materials/MaterialsPage.qml

@@ -126,7 +126,7 @@ UM.ManagementPage
         ScrollBar.vertical: UM.ScrollBar
         {
             id: materialScrollBar
-            parent: materialScrollView
+            parent: materialScrollView.parent
             anchors
             {
                 top: parent.top

resources/qml/Preferences/Materials/MaterialsView.qml

@@ -94,7 +94,7 @@ Item
             ScrollBar.vertical: UM.ScrollBar
             {
                 id: scrollBar
-                parent: informationPage
+                parent: informationPage.parent
                 anchors
                 {
                     top: parent.top
@@ -536,7 +536,7 @@ Item
             ScrollBar.vertical: UM.ScrollBar
             {
                 id: settingScrollBar
-                parent: settingsPage
+                parent: settingsPage.parent
                 anchors
                 {
                     top: parent.top

resources/qml/PrintMonitor.qml

@@ -21,7 +21,7 @@ ScrollView
     ScrollBar.vertical: UM.ScrollBar
     {
         id: scrollbar
-        parent: base
+        parent: base.parent
         anchors
         {
             right: parent.right