[HTML Imports] Make HTMLLinkElement.import a Document.

Source/core/html/HTMLLinkElement.cpp

Index: Source/core/html/HTMLLinkElement.cpp
diff --git a/Source/core/html/HTMLLinkElement.cpp b/Source/core/html/HTMLLinkElement.cpp
index bb331d9935612ceb9f6dea3c59695d9ba9a12d44..381f096bab17edbe82fb3ad73ed89b6293dde34c 100644
--- a/Source/core/html/HTMLLinkElement.cpp
+++ b/Source/core/html/HTMLLinkElement.cpp
@@ -173,10 +173,10 @@ LinkImport* HTMLLinkElement::linkImport() const
     return static_cast<LinkImport*>(m_link.get());
 }
 
-DocumentFragment* HTMLLinkElement::import() const
+Document* HTMLLinkElement::import() const
 {
     if (LinkImport* link = linkImport())
-        return linkImport()->importedFragment();
+        return linkImport()->importedDocument();
     return 0;
 }