fix applets hidden spacers calculations

--remove also some deprecated apis

containment/package/contents/ui/applet/AppletItem.qml

@@ -317,7 +317,7 @@ Item {
     property Item shortcuts: null
     property Item userRequests: null
 
-    property bool containsMouse: (parabolicAreaLoader.active && parabolicAreaLoader.item.containsMouse) || (isLattePlasmoid && latteApplet.containsMouse)
+    property bool containsMouse: parabolicAreaLoader.active && parabolicAreaLoader.item.containsMouse
     property bool pressed: viewSignalsConnector.pressed || clickedAnimation.running
 
 
@@ -903,7 +903,7 @@ Item {
         }
 
         // a hidden spacer on the right for the last item to add stability
-        HiddenSpacer{id: hiddenSpacerRight; rightSpacer: true}
+        HiddenSpacer{id: hiddenSpacerRight; isRightSpacer: true}
     }// Flow with hidden spacers inside
 
     //Busy Indicator

containment/package/contents/ui/applet/HiddenSpacer.qml

@@ -30,11 +30,11 @@ Item{
     height: root.isHorizontal ? wrapper.height : nHiddenSize
 
     ///check also if this is the first/last plasmoid in anylayout
-    visible: (rightSpacer ? appletItem.lastAppletInContainer : appletItem.firstAppletInContainer) || separatorSpace>0
+    visible: (isRightSpacer ? appletItem.lastAppletInContainer : appletItem.firstAppletInContainer) || separatorSpace>0
 
-    property bool neighbourSeparator: rightSpacer ? appletItem.headAppletIsSeparator : appletItem.tailAppletIsSeparator
+    property bool hasNeighbourSeparator: isRightSpacer ? appletItem.headAppletIsSeparator : appletItem.tailAppletIsSeparator
 
-    property int separatorSpace: neighbourSeparator && appletItem.parabolic.isEnabled ? LatteCore.WindowSystem.separatorLength / 2 : 0
+    property int separatorSpace: hasNeighbourSeparator && appletItem.parabolic.isEnabled ? LatteCore.Environment.separatorLength / 2 : 0
 
     property real nHiddenSize: {
         if (isSeparator || !communicator.requires.lengthMarginsEnabled) {
@@ -44,7 +44,7 @@ Item{
         return (nScale > 0) ? (appletItem.spacersMaxSize * nScale) + separatorSpace : separatorSpace
     }
 
-    property bool rightSpacer: false
+    property bool isRightSpacer: false
 
     property real nScale: 0