Fix Prepare/Cancel button visibility conditions for manual slicing

CURA-4525

resources/qml/SaveButton.qml

@@ -170,8 +170,8 @@ Item {
 
             tooltip: [1, 5].indexOf(base.backendState) != -1 ? catalog.i18nc("@info:tooltip","Slice current printjob") : catalog.i18nc("@info:tooltip","Cancel slicing process")
             // 1 = not started, 2 = Processing
-            enabled: base.backendState != "undefined" && (base.backendState == 1 || base.backendState == 2) && base.activity == true
-            visible: base.backendState != "undefined" && !autoSlice && (base.backendState == 1 || base.backendState == 2) && base.activity == true
+            enabled: base.backendState != "undefined" && ([1, 2].indexOf(base.backendState) != -1) && base.activity
+            visible: base.backendState != "undefined" && !autoSlice && ([1, 2, 4].indexOf(base.backendState) != -1) && base.activity
             property bool autoSlice
             height: UM.Theme.getSize("save_button_save_to_button").height
 
@@ -179,8 +179,8 @@ Item {
             anchors.right: parent.right
             anchors.rightMargin: UM.Theme.getSize("sidebar_margin").width
 
-            // 1 = not started, 5 = disabled
-            text: [1, 5].indexOf(base.backendState) != -1 ? catalog.i18nc("@label:Printjob", "Prepare") : catalog.i18nc("@label:Printjob", "Cancel")
+            // 1 = not started, 4 = error, 5 = disabled
+            text: [1, 4, 5].indexOf(base.backendState) != -1 ? catalog.i18nc("@label:Printjob", "Prepare") : catalog.i18nc("@label:Printjob", "Cancel")
             onClicked:
             {
                 sliceOrStopSlicing();