Make sure to save/restore scroll positions in finishDelayUpdateScrollInfo

third_party/WebKit/Source/core/layout/LayoutFlexibleBox.cpp

 /*
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 270 matching lines @@
         LayoutState state(*this, locationOffset());
 
         m_numberOfInFlowChildrenOnFirstLine = -1;
 
         LayoutBlock::startDelayUpdateScrollInfo();
 
         prepareOrderIteratorAndMargins();
 
         layoutFlexItems(relayoutChildren, layoutScope);
 
-        if (LayoutBlock::finishDelayUpdateScrollInfo(&layoutScope))
+        ScrollPositionMap scrollMap;
+        if (LayoutBlock::finishDelayUpdateScrollInfo(&layoutScope, &scrollMap)) {
             layoutFlexItems(false, layoutScope);
+            for (auto& entry : scrollMap) {
+                entry.key->scrollToPosition(entry.value);
+            }
+        }
 
         if (logicalHeight() != previousHeight)
             relayoutChildren = true;
 
         layoutPositionedObjects(relayoutChildren || isDocumentElement());
 
         // FIXME: css3/flexbox/repaint-rtl-column.html seems to issue paint invalidations for more overflow than it needs to.
         computeOverflow(clientLogicalBottomAfterRepositioning());
     }
 
@@ skipping 1359 matching lines @@
             ASSERT(child);
             LayoutUnit lineCrossAxisExtent = lineContexts[lineNumber].crossAxisExtent;
             LayoutUnit originalOffset = lineContexts[lineNumber].crossAxisOffset - crossAxisStartEdge;
             LayoutUnit newOffset = contentExtent - originalOffset - lineCrossAxisExtent;
             adjustAlignmentForChild(*child, newOffset - originalOffset);
         }
     }
 }
 
 } // namespace blink