Move scroll paint property nodes to be owned by the transform tree

third_party/WebKit/Source/core/paint/PaintPropertyTreePrinter.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/paint/PaintPropertyTreePrinter.h"
 
 #include "core/frame/FrameView.h"
 #include "core/frame/LocalFrame.h"
 #include "core/layout/LayoutPart.h"
 #include "core/layout/LayoutView.h"
@@ skipping 201 matching lines @@
       printer.addPropertyNode(effect, "Effect (" + object.debugName() + ")");
   }
 };
 
 template <>
 class PropertyTreePrinterTraits<ScrollPaintPropertyNode> {
  public:
   static void addFrameViewProperties(
       const FrameView& frameView,
       PropertyTreePrinter<ScrollPaintPropertyNode>& printer) {
-    if (const ScrollPaintPropertyNode* scroll = frameView.scroll())
-      printer.addPropertyNode(scroll, "Scroll (FrameView)");
+    if (const auto* scrollTranslation = frameView.scrollTranslation()) {
+      const auto* scrollNode = scrollTranslation->scrollNode();
+      printer.addPropertyNode(scrollNode, "Scroll (FrameView)");
+    }
   }
 
   static void addObjectPaintProperties(
       const LayoutObject& object,
       const ObjectPaintProperties& paintProperties,
       PropertyTreePrinter<ScrollPaintPropertyNode>& printer) {
-    if (const ScrollPaintPropertyNode* scroll = paintProperties.scroll())
-      printer.addPropertyNode(scroll, "Scroll (" + object.debugName() + ")");
+    if (const auto* scrollTranslation = paintProperties.scrollTranslation()) {
+      printer.addPropertyNode(scrollTranslation->scrollNode(),
+                              "Scroll (" + object.debugName() + ")");
+    }
   }
 };
 
 class PaintPropertyTreeGraphBuilder {
  public:
   PaintPropertyTreeGraphBuilder() {}
 
   void generateTreeGraph(const FrameView& frameView,
                          StringBuilder& stringBuilder) {
     m_layout.str("");
@@ skipping 180 matching lines @@
     const ClipPaintPropertyNode* overflowClip = properties->overflowClip();
     if (overflowClip) {
       if (const ClipPaintPropertyNode* innerBorderRadiusClip =
               properties->innerBorderRadiusClip())
         writePaintPropertyNode(*innerBorderRadiusClip, &object,
                                "innerBorderRadiusClip");
       writePaintPropertyNode(*overflowClip, &object, "overflowClip");
       if (object.isLayoutView() && overflowClip->parent())
         writePaintPropertyNode(*overflowClip->parent(), nullptr, "rootClip");
     }
-    const ScrollPaintPropertyNode* scroll = properties->scroll();
+
+    const auto* scroll =
+        scrollTranslation ? scrollTranslation->scrollNode() : nullptr;
     if (scroll)
       writePaintPropertyNode(*scroll, &object, "scroll");
   }
 
   template <typename PropertyTreeNode>
   static const PropertyTreeNode* getRoot(const PropertyTreeNode* node) {
     while (node && !node->isRoot())
       node = node->parent();
     return node;
   }
 
   void writeFrameViewPaintPropertyNodes(const FrameView& frameView) {
     if (const auto* contentsState =
             frameView.totalPropertyTreeStateForContents()) {
       if (const auto* root = getRoot(contentsState->transform()))
         writePaintPropertyNode(*root, &frameView, "rootTransform");
       if (const auto* root = getRoot(contentsState->clip()))
         writePaintPropertyNode(*root, &frameView, "rootClip");
       if (const auto* root = getRoot(contentsState->effect()))
         writePaintPropertyNode(*root, &frameView, "rootEffect");
-      if (const auto* root = getRoot(contentsState->scroll()))
-        writePaintPropertyNode(*root, &frameView, "rootScroll");
     }
     TransformPaintPropertyNode* preTranslation = frameView.preTranslation();
     if (preTranslation)
       writePaintPropertyNode(*preTranslation, &frameView, "preTranslation");
     TransformPaintPropertyNode* scrollTranslation =
         frameView.scrollTranslation();
     if (scrollTranslation)
       writePaintPropertyNode(*scrollTranslation, &frameView,
                              "scrollTranslation");
     ClipPaintPropertyNode* contentClip = frameView.contentClip();
     if (contentClip)
       writePaintPropertyNode(*contentClip, &frameView, "contentClip");
-    const ScrollPaintPropertyNode* scroll = frameView.scroll();
+    const auto* scroll =
+        scrollTranslation ? scrollTranslation->scrollNode() : nullptr;
     if (scroll)
       writePaintPropertyNode(*scroll, &frameView, "scroll");
   }
 
   void writeLayoutObjectNode(const LayoutObject& object) {
     std::ostream& os = m_layout;
     os << "n" << &object << " [color=" << s_layoutNodeColor
        << ", fontcolor=" << s_layoutNodeColor << ", label=\"" << object.name();
     Node* node = object.node();
     if (node) {
@@ skipping 96 matching lines @@
 }
 
 String paintPropertyTreeGraph(const blink::FrameView& frameView) {
   blink::PaintPropertyTreeGraphBuilder builder;
   StringBuilder stringBuilder;
   builder.generateTreeGraph(frameView, stringBuilder);
   return stringBuilder.toString();
 }
 
 #endif  // DCHECK_IS_ON()