Only create sticky position constraints for constrained sticky position.

third_party/WebKit/Source/core/frame/FrameView.cpp

 /*
  * Copyright (C) 1998, 1999 Torben Weis <weis@kde.org>
  *                     1999 Lars Knoll <knoll@kde.org>
  *                     1999 Antti Koivisto <koivisto@kde.org>
  *                     2000 Dirk Mueller <mueller@kde.org>
  * Copyright (C) 2004, 2005, 2006, 2007, 2008 Apple Inc. All rights reserved.
  *           (C) 2006 Graham Dennis (graham.dennis@gmail.com)
  *           (C) 2006 Alexey Proskuryakov (ap@nypop.com)
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
@@ skipping 1725 matching lines @@
       return true;
   }
   return false;
 }
 
 bool FrameView::invalidateViewportConstrainedObjects() {
   bool fastPathAllowed = true;
   for (const auto& viewportConstrainedObject : *m_viewportConstrainedObjects) {
     LayoutObject* layoutObject = viewportConstrainedObject;
     LayoutItem layoutItem = LayoutItem(layoutObject);
-    ASSERT(layoutItem.style()->hasViewportConstrainedPosition());
+    DCHECK(layoutItem.style()->hasViewportConstrainedPosition() ||
+           layoutItem.style()->hasStickyConstrainedPosition());
     ASSERT(layoutItem.hasLayer());
     PaintLayer* layer = LayoutBoxModel(layoutItem).layer();
 
     if (layer->isPaintInvalidationContainer())
       continue;
 
     if (layer->subtreeIsInvisible())
       continue;
 
     // invalidate even if there is an ancestor with a filter that moves pixels.
@@ skipping 3500 matching lines @@
 void FrameView::setAnimationHost(
     std::unique_ptr<CompositorAnimationHost> host) {
   m_animationHost = std::move(host);
 }
 
 LayoutUnit FrameView::caretWidth() const {
   return LayoutUnit(getHostWindow()->windowToViewportScalar(1));
 }
 
 }  // namespace blink