Samsung Electronics Co. has decided to pay part of executives’ bonuses in stock rather than cash for the first time, linking pay to share performance at a time the company is struggling with chipmaking.The company will pay a portion of the annual bonus in shares to executives starting January next year, according to an internal posting confirmed by the company. The stock portion of the bonus — previously all cash — varies from 50% to 100%, increasing in proportion to seniority. Company officials...