"He didn't flinch when the request came in." These are the words of a royal source, when asked if Prince William had shown any resistance to the UK government's request for him to visit Saudi Arabia. "He takes his role as Prince of Wales very seriously, so when the government asks, he goes," the source told me. But this trip - the prince's first to Saudi - is something of a diplomatic maze. Previous official visits to Estonia, Poland, Brazil and South Africa have not been as sensitive - Saudi