Implement attribute getters for IntersectionObserver.

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 45 matching lines @@
         LayoutRect clipRect(LayoutPoint(), LayoutSize(rootLayoutBox->layer()->size()));
         m_observer->applyRootMargin(clipRect);
         rootLayoutBox->flipForWritingMode(rect);
         rect.intersect(clipRect);
         rootLayoutBox->flipForWritingMode(rect);
     }
 }
 
 void IntersectionObservation::clipToFrameView(IntersectionGeometry& geometry)
 {
-    Node* rootNode = m_observer->root();
+    Node* rootNode = m_observer->rootNode();
     LayoutObject* rootLayoutObject = m_observer->rootLayoutObject();
     if (rootLayoutObject->isLayoutView()) {
         geometry.rootRect = LayoutRect(toLayoutView(rootLayoutObject)->frameView()->visibleContentRect());
         m_observer->applyRootMargin(geometry.rootRect);
         geometry.intersectionRect.intersect(geometry.rootRect);
     } else {
         if (rootLayoutObject->isBox())
             geometry.rootRect = LayoutRect(toLayoutBox(rootLayoutObject)->absoluteContentBox());
         else
             geometry.rootRect = LayoutRect(rootLayoutObject->absoluteBoundingBoxRect());
@@ skipping 100 matching lines @@
     m_observer.clear();
 }
 
 DEFINE_TRACE(IntersectionObservation)
 {
     visitor->trace(m_observer);
     visitor->trace(m_target);
 }
 
 } // namespace blink