Remove MediaQueryList listener from removed HTMLSourceElement.

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

 // Copyright 2014 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/html/HTMLPictureElement.h"
 
 #include "core/HTMLNames.h"
 #include "core/dom/ElementTraversal.h"
 #include "core/frame/UseCounter.h"
 #include "core/html/HTMLImageElement.h"
+#include "core/html/HTMLSourceElement.h"
 #include "core/loader/ImageLoader.h"
 
 namespace blink {
 
 using namespace HTMLNames;
 
 inline HTMLPictureElement::HTMLPictureElement(Document& document)
     : HTMLElement(pictureTag, document)
 {
 }
 
 DEFINE_NODE_FACTORY(HTMLPictureElement)
 
 void HTMLPictureElement::sourceOrMediaChanged()
 {
     for (HTMLImageElement* imageElement = Traversal<HTMLImageElement>::firstChild(*this); imageElement; imageElement = Traversal<HTMLImageElement>::nextSibling(*imageElement)) {
         imageElement->selectSourceURL(ImageLoader::UpdateNormal);
     }
 }
 
+void HTMLPictureElement::removeListenerFromSourceChildren()
+{
+    for (HTMLSourceElement* sourceElement = Traversal<HTMLSourceElement>::firstChild(*this); sourceElement; sourceElement = Traversal<HTMLSourceElement>::nextSibling(*sourceElement)) {
+        sourceElement->removeMediaQueryListListener();
+    }
+}
+
+void HTMLPictureElement::addListenerToSourceChildren()
+{
+    for (HTMLSourceElement* sourceElement = Traversal<HTMLSourceElement>::firstChild(*this); sourceElement; sourceElement = Traversal<HTMLSourceElement>::nextSibling(*sourceElement)) {
+        sourceElement->addMediaQueryListListener();
+    }
+}
+
+
 Node::InsertionNotificationRequest HTMLPictureElement::insertedInto(ContainerNode* insertionPoint)
 {
     UseCounter::count(document(), UseCounter::Picture);
     return HTMLElement::insertedInto(insertionPoint);
 }
 
 } // namespace blink