v3.4.4

Bugfixes:

• Fix benchmark parallel in node 6 #1165
• Fix memory leak with Promise.each #1057
• Fix thenable passed to .return being evaluated too early #1210
• Fix "unhandledrejection" event not having .detail field when using DOM3 event listener api #1209
• Fix Promise.join not ensuring asynchronous callback #1153
• Fix domains leaking when synchronous error is thrown while a domain is active #1125