CopyUnicodeTo( const nsReadingIterator<PRUnichar>& aSrcStart, const nsReadingIterator<PRUnichar>& aSrcEnd, nsAWritableString& aDest )
CopyUnicodeTo( const nsAString& aSource, PRUint32 aSrcOffset, PRUnichar* aDest, PRUint32 aLength )
CopyUnicodeTo( const nsReadingIterator<PRUnichar>& aSrcStart,               const nsReadingIterator<PRUnichar>& aSrcEnd,               nsAWritableString& aDest )  {    nsWritingIterator<PRUnichar> writer;    aDest.SetLength(Distance(aSrcStart, aSrcEnd));    aDest.BeginWriting(writer);    nsReadingIterator<PRUnichar> fromBegin(aSrcStart);        copy_string(fromBegin, aSrcEnd, writer);  }