QmlDesigner: Disable scrolling if content does fit

This is required on windows, because the other scrollbar seems
to be taken into account somehow.

Change-Id: I890faf7493c38df1f2f2f7fae011d4946f1b9c33
Reviewed-by: Henning Gründl <henning.gruendl@qt.io>

share/qtcreator/qmldesigner/newstateseditor/Main.qml

@@ -520,6 +520,16 @@ Rectangle {
                     orientation: Qt.Vertical
                 }
 
+                flickableDirection: {
+                    if (frame.contentHeight <= scrollView.height)
+                        return Flickable.HorizontalFlick
+
+                    if (frame.contentWidth <= scrollView.width)
+                        return Flickable.VerticalFlick
+
+                    return Flickable.HorizontalAndVerticalFlick
+                }
+
                 Flickable {
                     id: frame
                     boundsMovement: Flickable.StopAtBounds