Remove ordered list assumptions in PathView

When flicking fast or jumping around on paths with some items not seen,
the current algorithm makes assumptions about list ordering which are
hard to maintain. Specifically that it has the index of the first item
in the list cached and that all changed will be to either prepend or
append an item to the current ordered set.

This patch removes that assumption, leading to a little more work each
time to identify where new elements will go. There is still a slightly
faster path for the common case of adding elements to the beginning or
end of the path.

Task-number: QTBUG-42716
Change-Id: Ief76c93967d254d405e6656ef27d06b4ecc470c8
Reviewed-by: Jørgen Lind <jorgen.lind@theqtcompany.com>
Reviewed-by: Shawn Rutledge <shawn.rutledge@digia.com>

1 files changed, 0 insertions, 1 deletions

diff --git a/src/quick/items/qquickpathview_p_p.h b/src/quick/items/qquickpathview_p_p.h
index 35ea8616a5..2a497881d4 100644
--- a/src/quick/items/qquickpathview_p_p.h
+++ b/src/quick/items/qquickpathview_p_p.h
@@ -155,7 +155,6 @@ public:
     QQuickTimeLine tl;
     QQuickTimeLineValueProxy<QQuickPathViewPrivate> moveOffset;
     int flickDuration;
-    int firstIndex;
     int pathItems;
     int requestedIndex;
     int cacheSize;