Make view.domrange private; isRendered/isAttached
Make _onViewRendered private; onViewReady

The _onViewRendered hook fires when the View is actually rendered, not waiting until flush time or for the DOMRange to be attached.  It’s not very useful as part of the public API, because you can’t do anything with it (like manipulate the generated DOM).  Instead, expose onViewReady, which underlies the template “rendered” callback.
Fix DOMRange onAttached; view.{first,last}Node()

DOMRange#setMembers was causing DOMRange#onAttached callbacks to get called, masking a bug in onViewReady where DOMRange#attached was misspelled DOMRange#isAttached.