Since f411f3145b, these properties
no longer change with each loop. This however caused a regression
on the behavior of resetting loop count by resetting these
properties.
Previously, after the loop count is decreased, it is possible to
reset these properties back their original values and thus reset
the remaining loop count. Currently, because setting properties
has no effect if the new value is the same as the existing value
(which no longer changes), resetting these properties does nothing,
and remaining-*-loops (which are read-only) remain unchanged.
There is no way to reset them other than temporarily setting them
to a different value, which is awkward.
Fortunately, this can be fixed by marking these properties as
force_update, which always notifies changes when being set.
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