• AsyncFromSyncIterator made stricter, related mainly to AsyncIterator.from and AsyncIterator.prototype.flatMap
• Handling of optional .next arguments in (Async)Iterator methods is aligned with the current spec draft (mainly - ignoring the first passed to .next argument in built-in generators)
• Behavior of .next, .return, .throw methods on AsyncIterator helpers proxy iterators aligned with the current spec draft (built-in async generators) (mainly - some early errors moved to returned promises)
• Fixed some cases of safe iteration closing
• Fixed dependencies of some entry points