[1.5.x] Documented ArchiveIndexView's date_list context variable.

Refs #16218.

Backport of a0c67c6.

docs/ref/class-based-views/generic-date-based.txt

@@ -42,6 +42,20 @@ ArchiveIndexView
     * :class:`django.views.generic.dates.DateMixin`
     * :class:`django.views.generic.base.View`
 
+    **Context**
+
+    In addition to the context provided by
+    :class:`django.views.generic.list.MultipleObjectMixin` (via
+    :class:`django.views.generic.dates.BaseDateListView`), the template's
+    context will be:
+
+    * ``date_list``: A
+      :meth:`DateQuerySet<django.db.models.query.QuerySet.dates>` object
+      containing all years that have objects available according to
+      ``queryset``, represented as
+      :class:`datetime.datetime<python:datetime.datetime>` objects, in
+      descending order.
+
     **Notes**
 
     * Uses a default ``context_object_name`` of ``latest``.
@@ -109,7 +123,6 @@ YearArchiveView
         Determine if an object list will be returned as part of the context.
         Returns :attr:`~YearArchiveView.make_object_list` by default.
 
-
     **Context**
 
     In addition to the context provided by
@@ -118,7 +131,7 @@ YearArchiveView
     context will be:
 
     * ``date_list``: A
-      :meth:`DateQuerySet<django.db.models.query.QuerySet.dates>` object object
+      :meth:`DateQuerySet<django.db.models.query.QuerySet.dates>` object
       containing all months that have objects available according to
       ``queryset``, represented as
       :class:`datetime.datetime<python:datetime.datetime>` objects, in