Apply scroll offset and content box offset before recursing in mapAncestorToLocal

third_party/WebKit/Source/core/dom/IntersectionObservation.cpp

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "core/dom/IntersectionObservation.h"
 
 #include "core/dom/ElementRareData.h"
 #include "core/dom/IntersectionObserver.h"
 #include "core/frame/FrameView.h"
 #include "core/layout/LayoutBox.h"
@@ skipping 76 matching lines @@
         &layoutObject,
         FloatQuad(FloatRect(rect)),
         UseTransforms | ApplyContainerFlip | TraverseDocumentBoundaries);
     rect = LayoutRect(mappedQuad.boundingBox());
 }
 
 void IntersectionObservation::mapTargetRectToTargetFrameCoordinates(LayoutRect& rect) const
 {
     LayoutObject& targetLayoutObject = *target()->layoutObject();
     Document& targetDocument = target()->document();
-    LayoutSize scrollPosition = LayoutSize(toIntSize(targetDocument.view()->scrollPosition()));
+    LayoutSize scrollPosition = LayoutSize(targetDocument.view()->scrollOffset());
     mapRectUpToDocument(rect, targetLayoutObject, targetDocument);
     rect.move(-scrollPosition);
 }
 
 void IntersectionObservation::mapRootRectToRootFrameCoordinates(LayoutRect& rect) const
 {
     LayoutObject& rootLayoutObject = *m_observer->rootLayoutObject();
     Document& rootDocument = rootLayoutObject.document();
-    LayoutSize scrollPosition = LayoutSize(toIntSize(rootDocument.view()->scrollPosition()));
+    LayoutSize scrollPosition = LayoutSize(rootDocument.view()->scrollOffset());
     mapRectUpToDocument(rect, rootLayoutObject, rootLayoutObject.document());
     rect.move(-scrollPosition);
 }
 
 void IntersectionObservation::mapRootRectToTargetFrameCoordinates(LayoutRect& rect) const
 {
     LayoutObject& rootLayoutObject = *m_observer->rootLayoutObject();
     Document& targetDocument = target()->document();
-    LayoutSize scrollPosition = LayoutSize(toIntSize(targetDocument.view()->scrollPosition()));
+    LayoutSize scrollPosition = LayoutSize(targetDocument.view()->scrollOffset());
 
     if (&targetDocument == &rootLayoutObject.document())
         mapRectUpToDocument(rect, rootLayoutObject, targetDocument);
     else
         mapRectDownToDocument(rect, toLayoutBoxModelObject(rootLayoutObject), targetDocument);
 
     rect.move(-scrollPosition);
 }
 
 static bool isContainingBlockChainDescendant(LayoutObject* descendant, LayoutObject* ancestor)
@@ skipping 118 matching lines @@
     m_observer.clear();
 }
 
 DEFINE_TRACE(IntersectionObservation)
 {
     visitor->trace(m_observer);
     visitor->trace(m_target);
 }
 
 } // namespace blink