JPMorgan Chase (JPM) could slice the bonus of CEO Jamie Dimon, the highest-paid Wall Street chief, over the $6.2 billion "London Whale" trading debacle. The board of the nation's largest bank is reviewing compensation for Dimon, and Doug Braunstein, who was chief financial officer at the time the botched hedges came to light in May, the Wall Street Journal reported over the weekend. The bank could release its own internal report on the matter