Google Inc.’s IPO has been a boon for Time Warner. The New York media conglomerate, whose America Online unit acquired a stake in Google through a pre-IPO business partnership, sold a small chunk of that stake last year and still holds more than $1 billion worth of the Internet giant’s stock.The sale resulted in a pretax gain of $188 million, a portion of which was used to pay down debt, Time Warner Chief Financial Officer Wayne Pace said Friday during a conference call to discuss fourth-quarter financial results.For details click here