Move LayoutObject to satellite NodeLayoutData that hangs from a Node.

third_party/WebKit/Source/core/dom/Node.h

Index: third_party/WebKit/Source/core/dom/Node.h
diff --git a/third_party/WebKit/Source/core/dom/Node.h b/third_party/WebKit/Source/core/dom/Node.h
index d0ee8a6e2523a6946908c339f58cf6fc054cf7c1..f7dea5d17ce270cf587de6ed2316ff28751c905f 100644
--- a/third_party/WebKit/Source/core/dom/Node.h
+++ b/third_party/WebKit/Source/core/dom/Node.h
@@ -97,21 +97,30 @@ enum class SlotChangeType {
   kChained,
 };
 
-class NodeRareDataBase {
+class LayoutData {

[esprehn, 2017/04/10 22:20:12]

NodeLayoutData maybe? LayoutData is pretty generic, it's also a bit unfortunate
that this thing is both style and layout, I miss the days when we just called
this stuff Rendering :P But the bike shed is not super important.

[nainar, 2017/04/13 00:10:22]

Done.

  public:
+  LayoutData(LayoutObject* layout_object) : layout_object_(layout_object) {}

[esprehn, 2017/04/10 22:20:12]

explicit on all single arg constructors unless you want to allow implicit
construction, you probably don't want that here.

[nainar, 2017/04/13 00:10:22]

Done.

   LayoutObject* GetLayoutObject() const { return layout_object_; }
   void SetLayoutObject(LayoutObject* layout_object) {
     layout_object_ = layout_object;
   }
 
+ private:
+  LayoutObject* layout_object_;
+};
+
+class NodeRareDataBase {
+ public:
+  LayoutData* GetLayoutData() const { return layout_data_; }
+  void SetLayoutData(LayoutData* layout_data) { layout_data_ = layout_data; }
+
  protected:
-  NodeRareDataBase(LayoutObject* layout_object)
-      : layout_object_(layout_object) {}
+  NodeRareDataBase(LayoutObject* layout_object) {
+    layout_data_ = new LayoutData(layout_object);
+  }
 
  protected:
-  // LayoutObjects are fully owned by their DOM node. See LayoutObject's
-  // LIFETIME documentation section.
-  LayoutObject* layout_object_;
+  LayoutData* layout_data_;
 };
 
 class Node;
@@ -563,14 +572,14 @@ class CORE_EXPORT Node : public EventTarget {
   // Note that if a Node has a layoutObject, it's parentNode is guaranteed to
   // have one as well.
   LayoutObject* GetLayoutObject() const {
-    return HasRareData() ? data_.rare_data_->GetLayoutObject()
-                         : data_.layout_object_;
+    return HasRareData() ? data_.rare_data_->GetLayoutData()->GetLayoutObject()
+                         : data_.layout_data_->GetLayoutObject();
   }
   void SetLayoutObject(LayoutObject* layout_object) {
     if (HasRareData())
-      data_.rare_data_->SetLayoutObject(layout_object);
+      data_.rare_data_->GetLayoutData()->SetLayoutObject(layout_object);
     else
-      data_.layout_object_ = layout_object;
+      data_.layout_data_->SetLayoutObject(layout_object);
   }
 
   // Use these two methods with caution.
@@ -925,10 +934,10 @@ class CORE_EXPORT Node : public EventTarget {
   Member<Node> next_;
   // When a node has rare data we move the layoutObject into the rare data.
   union DataUnion {
-    DataUnion() : layout_object_(nullptr) {}
+    DataUnion() : layout_data_(nullptr) {}
     // LayoutObjects are fully owned by their DOM node. See LayoutObject's
     // LIFETIME documentation section.
-    LayoutObject* layout_object_;
+    LayoutData* layout_data_;
     NodeRareDataBase* rare_data_;
   } data_;
 };