CHILEOne of the most closely guarded secrets at the APEC summit in Japan’s port city of Yokohama this weekend is not what the Asia-Pacific leaders might say about currencies and global imbalances. No, that’s all going to be thrashed out at the G20 meeting Thursday and Friday in Seoul. The big topic of speculation here at the Pacifico Yokohama Convention Center is what the leaders will wear when they gather for the annual class photo that concludes the meetings.