Add 'exposed' objects and embeds to a document's named properties.

Source/core/html/HTMLObjectElement.cpp

Index: Source/core/html/HTMLObjectElement.cpp
diff --git a/Source/core/html/HTMLObjectElement.cpp b/Source/core/html/HTMLObjectElement.cpp
index 1d9a87adf4b710dde3c07f6c878c1e374f067b53..2851b34422bfea489ca82abb21e11f86c2c03595 100644
--- a/Source/core/html/HTMLObjectElement.cpp
+++ b/Source/core/html/HTMLObjectElement.cpp
@@ -386,6 +386,22 @@ void HTMLObjectElement::renderFallbackContent()
     reattachFallbackContent();
 }
 
+bool HTMLObjectElement::isExposed() const
+{
+    // http://www.whatwg.org/specs/web-apps/current-work/#exposed
+    for (Node* ancestor = parentNode(); ancestor; ancestor = ancestor->parentNode()) {

[abarth-chromium, 2013/11/18 17:38:58]

Are these ancestor traversals correct w.r.t. shadow DOM?  Can you add some tests
for the cases where there's a shadow DOM boundary between the <object> and an
ancestor <object>?

[sof, 2013/11/18 20:37:35]

Thanks. Does

  https://codereview.chromium.org/75273004/patch/40001/50004

address it? I'm on thin ice wrt shadow DOM know-how.

+        if (ancestor->hasTagName(objectTag) && toHTMLObjectElement(ancestor)->isExposed())
+            return false;
+    }
+    if (hasFallbackContent() && !useFallbackContent())
+        return true;
+    for (Node* node = firstChild(); node; node = NodeTraversal::next(*node, this)) {
+        if (node->hasTagName(objectTag) || node->hasTagName(embedTag))
+            return false;
+    }
+    return true;
+}
+
 bool HTMLObjectElement::containsJavaApplet() const
 {
     if (MIMETypeRegistry::isJavaAppletMIMEType(getAttribute(typeAttr)))