Extent change from initialExtent doesn't trigger canGoToPrevious change

[davetimmins]

Pan works as expected but not zooming in/out. The canGoToPrevious property doesn't update and so the UI doesn't correctly reflect the state, although the extent is still stored correctly.

[ycabon]

watching view.stationary would be better than view.interacting. stationary is a combo of !view.interacting and !view.animation.

[davetimmins]

Cool, that fixes both issues, only have to watch stationary and not viewpoint too. Storing the viewpoint though as you suggested.