With the U.S. presidential election only a year away, the two sides are trying to hammer out a relatively narrow, “phase-one” deal that Trump and his Chinese counterpart Xi Jinping planned to sign at a now-canceled Asia-Pacific summit in Chile next week. In the quest for a new location, China is seeking a roll back of tariffs before Xi agrees to take the politically risky step of heading to the U.S. to sign a deal….