A heavy slate of U.S. company results in the coming week will test a stock market shaken by a U.S. trade policy overhaul that upended the outlook for the global economy and corporate America. Investors remain on edge after President Donald Trump’s sweeping April 2 tariff announcement stunned markets and sparked some of the most volatile trading since the onset of the COVID-19 pandemic five years ago. After rebounding somewhat last week, the benchmark S&P 500 stock index fell this week and was down 14% from its February record high. Volatility levels moderated from five-year peaks but remain elevated by...