John Ternus, Apple’s senior vice president of hardware engineering, takes over as CEO on Sept. 1, ending Tim Cook’s 15-year tenure at the top of the world’s most valuable consumer technology company.  Apple’s presence with China is perhaps the defining relationship of the Tim Cook era. Chinese factories, managed by Global 500 companies like Foxconn and Luxshare, made the iPhones that turned the company into a global juggernaut. Chinese consumers also snapped up Apple products, making the country one of Apple’s most important markets. Cook was also a frequent visitor to Beijing, meeting senior officials and dropping by Apple stores…