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 1749 matching lines @@
   }
   return false;
 }
 
 bool FrameView::InvalidateViewportConstrainedObjects() {
   bool fast_path_allowed = true;
   for (const auto& viewport_constrained_object :
        *viewport_constrained_objects_) {
     LayoutObject* layout_object = viewport_constrained_object;
     LayoutItem layout_item = LayoutItem(layout_object);
-    ASSERT(layout_item.Style()->HasViewportConstrainedPosition());
-    ASSERT(layout_item.HasLayer());
+    DCHECK(layout_item.Style()->HasViewportConstrainedPosition() ||
+           layout_item.Style()->HasStickyConstrainedPosition());
+    DCHECK(layout_item.HasLayer());
     PaintLayer* layer = LayoutBoxModel(layout_item).Layer();
 
     if (layer->IsPaintInvalidationContainer())
       continue;
 
     if (layer->SubtreeIsInvisible())
       continue;
 
     // invalidate even if there is an ancestor with a filter that moves pixels.
     layout_item
@@ skipping 3549 matching lines @@
 void FrameView::SetAnimationHost(
     std::unique_ptr<CompositorAnimationHost> host) {
   animation_host_ = std::move(host);
 }
 
 LayoutUnit FrameView::CaretWidth() const {
   return LayoutUnit(GetHostWindow()->WindowToViewportScalar(1));
 }
 
 }  // namespace blink