Initial ResizeObserver implementation

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

Index: third_party/WebKit/Source/core/dom/Document.h
diff --git a/third_party/WebKit/Source/core/dom/Document.h b/third_party/WebKit/Source/core/dom/Document.h
index 27a0cd1e41d4ef9bb70af296dbb0a0dc596856d8..dce19897d2cf2cc4592a881b67db56bb94fd0389 100644
--- a/third_party/WebKit/Source/core/dom/Document.h
+++ b/third_party/WebKit/Source/core/dom/Document.h
@@ -142,6 +142,7 @@ class PlatformMouseEvent;
 class ProcessingInstruction;
 class QualifiedName;
 class Range;
+class ResizeObserverController;
 class ResourceFetcher;
 class RootScrollerController;
 class SVGDocumentExtensions;
@@ -707,6 +708,9 @@ public:
     IntersectionObserverController& ensureIntersectionObserverController();
     NodeIntersectionObserverData& ensureIntersectionObserverData();
 
+    ResizeObserverController* resizeObserverController() const { return m_resizeObserverController; }
+    ResizeObserverController& ensureResizeObserverController();
+
     void updateViewportDescription();
 
     // Returns the owning element in the parent document. Returns nullptr if
@@ -1412,6 +1416,7 @@ private:
 
     Member<IntersectionObserverController> m_intersectionObserverController;
     Member<NodeIntersectionObserverData> m_intersectionObserverData;
+    Member<ResizeObserverController> m_resizeObserverController;
 
     int m_nodeCount;