Wrong update contentY if operate with first item in ListView

When qml ListView has more items then can be visible on screen and so can be scrolled and ListView is placed in the top of view ('contentY' = 0) then:

1. Removing first item from qml ListView model increases 'contentY' value on height of removed item ('contentY' += item.height). Every like removing first item increase 'contentY' wrong on item height and scrolling begin to work very very bad.

2. Moving any item to first position increases 'contentY' value on 'y' position of moved item ('contentY' += item.y). Every like moving item to first position increases 'contentY' wrong on moved item 'y' position and scrolling begin to work very very bad.

In this both cases Item 'y' position has failed offset on failed 'contentY' value but 'indexAt()' works correct. Reset 'contentY' to 0 does not help and move list down. Scroll begins to work very unstable and we have different 'contentY' and 'visibleArea.yPosition * contentHeight' values.