Adding new tab handling and focus support.

git-svn-id: svn://10.0.0.236/trunk@22599 18797224-902f-48f8-a5cc-f745e15eee43

mozilla/layout/base/src/nsDocument.cpp

@@ -726,6 +726,8 @@ nsDocument::Reset(nsIURL *aURL)
   }
 
   if (nsnull != mRootContent) {
+    // Ensure that document is nsnull to allow validity checks on content
+    mRootContent->SetDocument(nsnull, PR_TRUE);
     ContentRemoved(nsnull, mRootContent, 0);
     NS_IF_RELEASE(mRootContent);
   }