do not start sliding ins/outs with no reason

--ViewPart:VisibilityManager is sending events
to show or hide but it can not validate the view
visual state meaning is hidden, sliding in/out, blocked
etc. That role is taken from Containment::VisibilityManager
that accepts that signals and in case the state are
requesting is already provided then in such case
these signals are ignored.
--This way myView flags for inSlidingIn/Out/PartiallyShown/FullyShown
etc are providing valid values in some previous
problematic scenarios
--This fix solves the issue that parabolic effect with Tasks Previews
it was not too responsive but it had many glitches

containment/package/contents/ui/VisibilityManager.qml

@@ -536,7 +536,9 @@ Item{
         }
 
         //! Normal Dodge/AutoHide case
-        if (!slidingAnimationAutoHiddenIn.running && !inRelocationHiding){
+        if (!slidingAnimationAutoHiddenIn.running
+                && !inRelocationHiding
+                && (latteView.visibility.isHidden || slidingAnimationAutoHiddenOut.running /*it is not already shown or is trying to hide*/)){
             slidingAnimationAutoHiddenIn.init();
         }
     }
@@ -555,7 +557,8 @@ Item{
         //! Normal Dodge/AutoHide case
         if (!slidingAnimationAutoHiddenOut.running
                 && !latteView.visibility.blockHiding
-                && !latteView.visibility.containsMouse) {
+                && (!latteView.visibility.containsMouse || latteView.visibility.mode === LatteCore.Types.SidebarOnDemand /*for SidebarOnDemand mouse should be ignored on hiding*/)
+                && (!latteView.visibility.isHidden || slidingAnimationAutoHiddenIn.running /*it is not already hidden or is trying to show*/)) {
             slidingAnimationAutoHiddenOut.init();
         }
     }