A default time slice provider implementation that will always return one of the original time
slices of the feature. Null is returned if the feature does not have any time slices.
This provider uses the
method of the
interface that is implemented by
to retrieve the first shape in the
list of shapes. By default this list only contains baseline and snapshot time slices, but this
can be changed by changing the geometry filter of the feature.
If the shape count of the feature is 0, the first time slice in the list of time slices is
returned. This should also be a baseline or snapshot time slice in case the time slices in the
feature are sorted.