<picture>: Update the <img> element when a <source> changes

Source/core/html/HTMLSourceElement.cpp

Index: Source/core/html/HTMLSourceElement.cpp
diff --git a/Source/core/html/HTMLSourceElement.cpp b/Source/core/html/HTMLSourceElement.cpp
index 6c613b47a50fc021c7edb8c8a910331f38f80fc6..7f7f52e42a26450eb4cbb89180239acb7cf4f901 100644
--- a/Source/core/html/HTMLSourceElement.cpp
+++ b/Source/core/html/HTMLSourceElement.cpp
@@ -29,6 +29,7 @@
 #include "HTMLNames.h"
 #include "core/events/EventSender.h"
 #include "core/html/HTMLMediaElement.h"
+#include "core/html/HTMLPictureElement.h"
 #include "platform/Logging.h"
 
 using namespace std;
@@ -66,6 +67,8 @@ Node::InsertionNotificationRequest HTMLSourceElement::insertedInto(ContainerNode
     Element* parent = parentElement();
     if (isHTMLMediaElement(parent))
         toHTMLMediaElement(parent)->sourceWasAdded(this);
+    if (isHTMLPictureElement(parent))
+        toHTMLPictureElement(parent)->sourceOrMediaChanged();
     return InsertionDone;
 }
 
@@ -76,6 +79,8 @@ void HTMLSourceElement::removedFrom(ContainerNode* removalRoot)
         parent = toElement(removalRoot);
     if (isHTMLMediaElement(parent))
         toHTMLMediaElement(parent)->sourceWasRemoved(this);
+    if (isHTMLPictureElement(parent))
+        toHTMLPictureElement(parent)->sourceOrMediaChanged();
     HTMLElement::removedFrom(removalRoot);
 }
 
@@ -118,4 +123,14 @@ bool HTMLSourceElement::isURLAttribute(const Attribute& attribute) const
     return attribute.name() == srcAttr || HTMLElement::isURLAttribute(attribute);
 }
 
+void HTMLSourceElement::parseAttribute(const QualifiedName& name, const AtomicString& value)
+{
+    HTMLElement::parseAttribute(name, value);
+    if (name == srcsetAttr || name == sizesAttr || name == mediaAttr || name == typeAttr) {
+        Element* parent = parentElement();
+        if (isHTMLPictureElement(parent))
+            toHTMLPictureElement(parent)->sourceOrMediaChanged();
+    }
+}
+
 }