* Auto-pan settings currently only activate when the position of the
Overlay is set and the Overlay is already on a Map.
* The consequence of this is that creating an Overlay with position
set and then adding to a Map results in no auto-pan being performed -
it is necessary to first create the Overlay, then add to a Map and
finally set the position in order for the Map to auto-pan.
* This commit changes this behaviour so that the auto-pan settings are
also considered when the map property of the Overlay is set and not
only when the position property is set, leading to a more intuitive
behaviour.
* Fixes Issue #10843
* If panIntoView is an API method, it may now be called when the
position of the overlay has not yet been set.
* Adds a check for a set position to the panIntoView() method,
and removes the now unneccessary check in handlePositionChanged()
* Follow the suggestion from @ahocevar to use the existing
autoPan constructor option instead of creating a new autoPanOptions
option
* Internally also store the autoPanOptions in autoPan
* animation and margin encapsulated in a single object to allow
easier extension in future
* Constructor options extended to allow single object for
autoPan; separate options still allowed but deprecated
* Protected fields for animation and margin replaced with single
field
* As described in #10158, Control uses the property target_ for
a custom parent HTMLElement, leading to Events on the Control being
dispatched with that as the target and not the Control itself.
* Solved by renaming the target_ property on Target to eventTarget_
Edward Nash