Features

• finer pruning of switch branch (498ac83, bf76e35, 21fc8f4, 7880568)
• improve detection of superfluous assignment (fd8dec6)
• extend simplification of boolean expression (7c5b6f3, 980dbde)
• implement workaround for Safari/WebKit var bug (82772cc)

Bug Fixes

• assignment operator (111366f, 8b05677)
• await operator (6fc7a2a, e9c902b)
• class literal (ce75477, e368d39)
• default parameter (e70b848)
• destructuring syntax (e70b848)
• function literal (7cbcd11, 1a064b6, 7621527)
• import statement (f8b2215)
• lexical declaration (95090db)
• spread syntax (ac1262d)
• yield keyword (e9c902b)