decouple background layer plasma shadows svg

--the multilayered background first layer is not
decoupled and is not the parent layer for all the
rest layer. This way we can really hide it without
influence the rest background layers.

containment/package/contents/ui/background/MultiLayered.qml

@@ -242,22 +242,12 @@ BackgroundProperties{
         id: shadowsSvgItem
         width: root.isVertical ?  background.thickness + totals.shadowsThickness : totals.visualLength
         height: root.isVertical ? totals.visualLength : background.thickness + totals.shadowsThickness
-
+        enabledBorders: latteView && latteView.effects ? latteView.effects.enabledBorders : PlasmaCore.FrameSvg.NoBorder
         imagePath: "widgets/panel-background"
         prefix: "shadow"
-
+        opacity: hideShadow || !root.useThemePanel || (root.forceTransparentPanel && !root.forcePanelForBusyBackground) ? 0 : 1
         visible: (opacity == 0) ? false : true
 
-        opacity: {
-            if ((root.forceTransparentPanel && !root.forcePanelForBusyBackground)
-                    || !root.useThemePanel)
-                return 0;
-            else
-                return 1;
-        }
-
-        enabledBorders: latteView && latteView.effects && !hideShadow ? latteView.effects.enabledBorders : PlasmaCore.FrameSvg.NoBorder
-
         //! set true by default in order to avoid crash on startup because imagePath is set to ""
         readonly property bool themeHasShadow: themeExtended ? themeExtended.hasShadow : true
 
@@ -287,6 +277,7 @@ BackgroundProperties{
             enabled: !LatteCore.WindowSystem.compositingActive
             NumberAnimation { duration: 0 }
         }
+    }
 
     //! Layer 2: Provide visual solidness. Plasma themes by design may provide a panel-background svg that is not
     //!          solid. That means that user can not gain full solidness in such cases. This layer is responsible
@@ -323,7 +314,7 @@ BackgroundProperties{
         anchors.rightMargin: LatteCore.WindowSystem.compositingActive ? shadows.right : 0
         anchors.topMargin: LatteCore.WindowSystem.compositingActive ? shadows.top : 0
         anchors.bottomMargin: LatteCore.WindowSystem.compositingActive ? shadows.bottom : 0
-            anchors.fill:parent
+        anchors.fill: shadowsSvgItem
 
         opacity: normalizedOpacity
 
@@ -584,7 +575,7 @@ BackgroundProperties{
         borderColor: "red"
         roundness: overlayedBackground.roundness
     }*/
-    }
+
 
     //BEGIN states
     //user set Panel Positions