When Waltham-based Raytheon Co. (NYSE: RTN) reports third quarter earnings on Thursday, the defense contractor could face questions about diplomatic risks to its lucrative business in Saudi Arabia, where it's sought to expand in recent years. Raytheon's stock price is already down 7.5 percent since October 9, the day news reports indicated that Turkish officials would search the Saudi Consulate in Istanbul after the disappearance of journalist Jamal Khashoggi.