tc->CopyText(text);
tc->AppendTextTo(text);
CompressWhitespace(nsIContent* aContent){  PRUint32 numKids = aContent->GetChildCount();  for (PRUint32 kid = 0; kid < numKids; kid++) {    nsCOMPtr<nsITextContent> tc(do_QueryInterface(aContent->GetChildAt(kid)));    if (tc && tc->IsContentOfType(nsIContent::eTEXT)) {      nsAutoString text;      tc->CopyText(text);      text.CompressWhitespace();      tc->SetText(text, PR_FALSE); // not meant to be used if notify is needed    }  }}