. . . Whittaker Corp. of Los Angeles said shareholders approved a plan to reincorporate in Delaware . . . Progressive Savings & Loan in Alhambra said it has reached a definite agreement with Greenfield Partners, a New York investment partnership, whereby Greenfield will acquire control of the savings and loan for $10 million . . . Activision, a leading producer and marketer of home computer software, said it has completed the acquisition of Infocom of Cambridge, Mass., which produces entertainment software . . . Warner-Lambert said it has completed the sale of its IMED subsidiary, a developer and marketer of devices that administer intravenous solutions to hospital patients, to Henley Group for $163.5 million in cash.