Initial ResizeObserver implementation

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

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Peter Kelly (pmk@post.com)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2007 David Smith (catfish.man@gmail.com)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012, 2013 Apple Inc. All rights reserved.
  *           (C) 2007 Eric Seidel (eric@webkit.org)
  *
  * This library is free software; you can redistribute it and/or
@@ skipping 2605 matching lines @@
     if (elementRareData())
         return elementRareData()->intersectionObserverData();
     return nullptr;
 }
 
 NodeIntersectionObserverData& Element::ensureIntersectionObserverData()
 {
     return ensureElementRareData().ensureIntersectionObserverData();
 }
 
+ResizeObservationSet& Element::ensureResizeObserverData()
+{
+    return ensureElementRareData().ensureResizeObserverData();
+}
+
 // Step 1 of http://domparsing.spec.whatwg.org/#insertadjacenthtml()
 static Element* contextElementForInsertion(const String& where, Element* element, ExceptionState& exceptionState)
 {
     if (equalIgnoringCase(where, "beforeBegin") || equalIgnoringCase(where, "afterEnd")) {
         Element* parent = element->parentElement();
         if (!parent) {
             exceptionState.throwDOMException(NoModificationAllowedError, "The element has no parent.");
             return nullptr;
         }
         return parent;
@@ skipping 1071 matching lines @@
 
 DEFINE_TRACE_WRAPPERS(Element)
 {
     if (hasRareData()) {
         visitor->traceWrappers(elementRareData());
     }
     ContainerNode::traceWrappers(visitor);
 }
 
 } // namespace blink