Have DOMPatchSupport and DocumentFragment deal with Document references

Source/core/platform/Pasteboard.cpp

Index: Source/core/platform/Pasteboard.cpp
diff --git a/Source/core/platform/Pasteboard.cpp b/Source/core/platform/Pasteboard.cpp
index 9a391e16864d8d56e5e5b98069bcec7578b30e02..1a7f356a36bb92c1d14514320be23db9e4af65c7 100644
--- a/Source/core/platform/Pasteboard.cpp
+++ b/Source/core/platform/Pasteboard.cpp
@@ -173,7 +173,8 @@ PassRefPtr<DocumentFragment> Pasteboard::documentFragment(Frame* frame, PassRefP
         WebKit::WebURL url;
         WebKit::WebString markup = WebKit::Platform::current()->clipboard()->readHTML(buffer, &url, &fragmentStart, &fragmentEnd);
         if (!markup.isEmpty()) {
-            if (RefPtr<DocumentFragment> fragment = createFragmentFromMarkupWithContext(frame->document(), markup, fragmentStart, fragmentEnd, KURL(url), DisallowScriptingAndPluginContent))
+            ASSERT(frame->document());
+            if (RefPtr<DocumentFragment> fragment = createFragmentFromMarkupWithContext(*frame->document(), markup, fragmentStart, fragmentEnd, KURL(url), DisallowScriptingAndPluginContent))
                 return fragment.release();
         }
     }