Don't recolor printer status buttons

Just leave it to the actual icons to provide colour. It may be a bit harder to modify the colours in a different theme then, but now we can have multi-colour icons (as per the new theme requires).

Contributes to issue CURA-4148.

resources/qml/Topbar.qml

@@ -59,38 +59,6 @@ Rectangle
             onClicked: base.startMonitoringPrint()
             text: catalog.i18nc("@title:tab", "Print")
             iconSource: UM.Theme.getIcon("tab_monitor")
-            property color overlayColor:
-            {
-                if(!printerAcceptsCommands)
-                {
-                    return UM.Theme.getColor("status_unknown");
-                }
-
-                if(Cura.MachineManager.printerOutputDevices[0].printerState == "maintenance")
-                {
-                    return UM.Theme.getColor("status_busy");
-                }
-                switch(Cura.MachineManager.printerOutputDevices[0].jobState)
-                {
-                    case "printing":
-                    case "pre_print":
-                    case "wait_cleanup":
-                    case "pausing":
-                    case "resuming":
-                        return UM.Theme.getColor("status_busy");
-                    case "ready":
-                    case "":
-                        return UM.Theme.getColor("status_ready");
-                    case "paused":
-                        return UM.Theme.getColor("status_paused");
-                    case "error":
-                        return UM.Theme.getColor("status_stopped");
-                    case "offline":
-                        return UM.Theme.getColor("status_offline");
-                    default:
-                        return UM.Theme.getColor("text_emphasis");
-                }
-            }
             property string overlayIconSource:
             {
                 if(!printerConnected)

resources/themes/cura/styles.qml

@@ -148,10 +148,9 @@ QtObject {
 
                         sourceSize: Theme.getSize("button_icon")
                     }
-                    UM.RecolorImage
+                    Image
                     {
                         visible: control.overlayIconSource != ""
-                        color: control.overlayColor
                         opacity: !control.enabled ? 0.2 : 1.0
                         source: control.overlayIconSource
                         width: Theme.getSize("button_icon").width