third_party/WebKit/Source/core/html/HTMLShadowElement.cpp

/*
 * Copyright (C) 2012 Google Inc. All rights reserved.
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#include "core/html/HTMLShadowElement.h"

#include "core/HTMLNames.h"
#include "core/dom/Document.h"
#include "core/dom/shadow/ShadowRoot.h"
#include "core/frame/UseCounter.h"
#include "core/inspector/ConsoleMessage.h"

namespace blink {

class Document;

inline HTMLShadowElement::HTMLShadowElement(Document& document)
    : InsertionPoint(HTMLNames::shadowTag, document) {
  UseCounter::count(document, UseCounter::HTMLShadowElement);
}

DEFINE_NODE_FACTORY(HTMLShadowElement)

HTMLShadowElement::~HTMLShadowElement() {}

ShadowRoot* HTMLShadowElement::olderShadowRoot() {
  ShadowRoot* containingRoot = containingShadowRoot();
  if (!containingRoot)
    return nullptr;

  updateDistribution();

  ShadowRoot* older = containingRoot->olderShadowRoot();
  if (!older || !older->isOpenOrV0() ||
      older->shadowInsertionPointOfYoungerShadowRoot() != this)
    return nullptr;

  DCHECK(older->isOpenOrV0());
  return older;
}

Node::InsertionNotificationRequest HTMLShadowElement::insertedInto(
    ContainerNode* insertionPoint) {
  if (insertionPoint->isConnected()) {
    // Warn if trying to reproject between user agent and author shadows.
    ShadowRoot* root = containingShadowRoot();
    if (root && root->olderShadowRoot() &&
        root->type() != root->olderShadowRoot()->type()) {
      String message =
          String::format("<shadow> doesn't work for %s element host.",
                         root->host().tagName().utf8().data());
      document().addConsoleMessage(ConsoleMessage::create(
          RenderingMessageSource, WarningMessageLevel, message));
    }
  }
  return InsertionPoint::insertedInto(insertionPoint);
}

}  // namespace blink